Lincoln Electric Welder SVM160 B User Manual

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SVM160-B  
April, 2005  
POWER MIG 300  
For use with machine Code Numbers: 10562, 10952, 10958, 11000, 11097, 11098  
For use with machine  
Safety Depends on You  
Lincoln arc welding and cutting  
equipment is designed and built  
with safety in mind. However, your  
overall safety can be increased by  
proper installation ... and thought-  
ful operation on your part. DO  
NOT INSTALL, OPERATE OR  
REPAIR THIS EQUIPMENT  
WITHOUT READING THIS  
MANUAL AND THE SAFETY  
PRECAUTIONS CONTAINED  
THROUGHOUT. And, most  
importantly, think before you act  
and be careful.  
SERVICE MANUAL  
Copyright © 2005 Lincoln Global Inc.  
• World's Leader in Welding and Cutting Products •  
• Sales and Service through Subsidiaries and Distributors Worldwide •  
Cleveland, Ohio 44117-1199 U.S.A. TEL: 216.481.8100 FAX: 216.486.1751 WEB SITE: www.lincolnelectric.com  
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ii  
ii  
SAFETY  
ELECTRIC SHOCK can  
ARC RAYS can burn.  
4.a. Use a shield with the proper filter and cover  
plates to protect your eyes from sparks and  
the rays of the arc when welding or observing  
open arc welding. Headshield and filter lens  
should conform to ANSI Z87. I standards.  
kill.  
3.a. The electrode and work (or ground) circuits  
are electrically “hot” when the welder is on.  
Do not touch these “hot” parts with your bare  
skin or wet clothing. Wear dry, hole-free  
gloves to insulate hands.  
4.b. Use suitable clothing made from durable flame-resistant  
material to protect your skin and that of your helpers from  
the arc rays.  
3.b. Insulate yourself from work and ground using dry insulation.  
Make certain the insulation is large enough to cover your full  
area of physical contact with work and ground.  
4.c. Protect other nearby personnel with suitable, non-flammable  
screening and/or warn them not to watch the arc nor expose  
themselves to the arc rays or to hot spatter or metal.  
In addition to the normal safety precautions, if welding  
must be performed under electrically hazardous  
conditions (in damp locations or while wearing wet  
clothing; on metal structures such as floors, gratings or  
scaffolds; when in cramped positions such as sitting,  
kneeling or lying, if there is a high risk of unavoidable or  
accidental contact with the workpiece or ground) use  
the following equipment:  
FUMES AND GASES  
can be dangerous.  
5.a. Welding may produce fumes and gases  
hazardous to health. Avoid breathing these  
• Semiautomatic DC Constant Voltage (Wire) Welder.  
• DC Manual (Stick) Welder.  
fumes and gases.When welding, keep  
your head out of the fume. Use enough  
• AC Welder with Reduced Voltage Control.  
ventilation and/or exhaust at the arc to keep  
fumes and gases away from the breathing zone. When  
welding with electrodes which require special  
ventilation such as stainless or hard facing (see  
instructions on container or MSDS) or on lead or  
cadmium plated steel and other metals or coatings  
which produce highly toxic fumes, keep exposure as  
low as possible and below Threshold Limit Values (TLV)  
using local exhaust or mechanical ventilation. In  
confined spaces or in some circumstances, outdoors, a  
respirator may be required. Additional precautions are  
also required when welding on galvanized steel.  
3.c. In semiautomatic or automatic wire welding, the electrode,  
electrode reel, welding head, nozzle or semiautomatic  
welding gun are also electrically “hot”.  
3.d. Always be sure the work cable makes a good electrical  
connection with the metal being welded. The connection  
should be as close as possible to the area being welded.  
3.e. Ground the work or metal to be welded to a good electrical  
(earth) ground.  
5.b. Do not weld in locations near chlorinated hydrocarbon vapors  
coming from degreasing, cleaning or spraying operations.  
The heat and rays of the arc can react with solvent vapors to  
form phosgene, a highly toxic gas, and other irritating prod-  
ucts.  
3.f. Maintain the electrode holder, work clamp, welding cable and  
welding machine in good, safe operating condition. Replace  
damaged insulation.  
3.g. Never dip the electrode in water for cooling.  
5.c. Shielding gases used for arc welding can displace air and  
cause injury or death. Always use enough ventilation,  
especially in confined areas, to insure breathing air is safe.  
3.h. Never simultaneously touch electrically “hot” parts of  
electrode holders connected to two welders because voltage  
between the two can be the total of the open circuit voltage  
of both welders.  
5.d. Read and understand the manufacturer’s instructions for this  
equipment and the consumables to be used, including the  
material safety data sheet (MSDS) and follow your  
employer’s safety practices. MSDS forms are available from  
your welding distributor or from the manufacturer.  
3.i. When working above floor level, use a safety belt to protect  
yourself from a fall should you get a shock.  
3.j. Also see Items 6.c. and 8.  
5.e. Also see item 1.b.  
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iii  
iii  
SAFETY  
WELDING SPARKS can  
cause fire or explosion.  
CYLINDER may explode  
if damaged.  
6.a. Remove fire hazards from the welding area.  
If this is not possible, cover them to prevent  
7.a. Use only compressed gas cylinders  
containing the correct shielding gas for the  
the welding sparks from starting a fire.  
Remember that welding sparks and hot  
materials from welding can easily go through small cracks  
and openings to adjacent areas. Avoid welding near  
hydraulic lines. Have a fire extinguisher readily available.  
process used and properly operating  
regulators designed for the gas and  
pressure used. All hoses, fittings, etc. should be suitable for  
the application and maintained in good condition.  
7.b. Always keep cylinders in an upright position securely  
chained to an undercarriage or fixed support.  
6.b. Where compressed gases are to be used at the job site,  
special precautions should be used to prevent hazardous  
situations. Refer to “Safety in Welding and Cutting” (ANSI  
Standard Z49.1) and the operating information for the  
equipment being used.  
7.c. Cylinders should be located:  
Away from areas where they may be struck or subjected to  
physical damage.  
6.c. When not welding, make certain no part of the electrode  
circuit is touching the work or ground. Accidental contact  
can cause overheating and create a fire hazard.  
•A safe distance from arc welding or cutting operations and  
any other source of heat, sparks, or flame.  
7.d. Never allow the electrode, electrode holder or any other  
electrically “hot” parts to touch a cylinder.  
6.d. Do not heat, cut or weld tanks, drums or containers until the  
proper steps have been taken to insure that such procedures  
will not cause flammable or toxic vapors from substances  
inside. They can cause an explosion even though they have  
been “cleaned”. For information, purchase “Recommended  
Safe Practices for the Preparation for Welding and Cutting of  
Containers and Piping That Have Held Hazardous  
Substances”, AWS F4.1 from the American Welding Society  
(see address above).  
7.e. Keep your head and face away from the cylinder valve outlet  
when opening the cylinder valve.  
7.f. Valve protection caps should always be in place and hand  
tight except when the cylinder is in use or connected for  
use.  
7.g. Read and follow the instructions on compressed gas  
cylinders, associated equipment, and CGA publication P-l,  
“Precautions for Safe Handling of Compressed Gases in  
Cylinders,” available from the Compressed Gas Association  
1235 Jefferson Davis Highway, Arlington, VA 22202.  
6.e. Vent hollow castings or containers before heating, cutting or  
welding. They may explode.  
6.f. Sparks and spatter are thrown from the welding arc. Wear oil  
free protective garments such as leather gloves, heavy shirt,  
cuffless trousers, high shoes and a cap over your hair. Wear  
ear plugs when welding out of position or in confined places.  
Always wear safety glasses with side shields when in a  
welding area.  
FOR ELECTRICALLY  
powered equipment.  
6.g. Connect the work cable to the work as close to the welding  
area as practical. Work cables connected to the building  
framework or other locations away from the welding area  
increase the possibility of the welding current passing  
through lifting chains, crane cables or other alternate cir-  
cuits. This can create fire hazards or overheat lifting chains  
or cables until they fail.  
8.a. Turn off input power using the disconnect  
switch at the fuse box before working on  
the equipment.  
8.b. Install equipment in accordance with the U.S. National  
Electrical Code, all local codes and the manufacturer’s  
recommendations.  
6.h. Also see item 1.c.  
8.c. Ground the equipment in accordance with the U.S. National  
Electrical Code and the manufacturer’s recommendations.  
POWER MIG 300  
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iv  
iv  
SAFETY  
5. Toujours porter des lunettes de sécurité dans la zone de  
soudage. Utiliser des lunettes avec écrans lateraux dans les  
zones où l’on pique le laitier.  
PRÉCAUTIONS DE SÛRETÉ  
Pour votre propre protection lire et observer toutes les instructions  
et les précautions de sûreté specifiques qui parraissent dans ce  
manuel aussi bien que les précautions de sûreté générales suiv-  
antes:  
6. Eloigner les matériaux inflammables ou les recouvrir afin de  
prévenir tout risque d’incendie dû aux étincelles.  
7. Quand on ne soude pas, poser la pince à une endroit isolé de  
la masse. Un court-circuit accidental peut provoquer un  
échauffement et un risque d’incendie.  
Sûreté Pour Soudage A L’Arc  
1. Protegez-vous contre la secousse électrique:  
a. Les circuits à l’électrode et à la piéce sont sous tension  
quand la machine à souder est en marche. Eviter toujours  
tout contact entre les parties sous tension et la peau nue  
ou les vétements mouillés. Porter des gants secs et sans  
trous pour isoler les mains.  
8. S’assurer que la masse est connectée le plus prés possible  
de la zone de travail qu’il est pratique de le faire. Si on place  
la masse sur la charpente de la construction ou d’autres  
endroits éloignés de la zone de travail, on augmente le risque  
de voir passer le courant de soudage par les chaines de lev-  
age, câbles de grue, ou autres circuits. Cela peut provoquer  
des risques d’incendie ou d’echauffement des chaines et des  
câbles jusqu’à ce qu’ils se rompent.  
b. Faire trés attention de bien s’isoler de la masse quand on  
soude dans des endroits humides, ou sur un plancher  
metallique ou des grilles metalliques, principalement dans  
les positions assis ou couché pour lesquelles une grande  
partie du corps peut être en contact avec la masse.  
c. Maintenir le porte-électrode, la pince de masse, le câble  
de soudage et la machine à souder en bon et sûr état  
defonctionnement.  
9. Assurer une ventilation suffisante dans la zone de soudage.  
Ceci est particuliérement important pour le soudage de tôles  
galvanisées plombées, ou cadmiées ou tout autre métal qui  
produit des fumeés toxiques.  
d.Ne jamais plonger le porte-électrode dans l’eau pour le  
refroidir.  
10. Ne pas souder en présence de vapeurs de chlore provenant  
d’opérations de dégraissage, nettoyage ou pistolage. La  
chaleur ou les rayons de l’arc peuvent réagir avec les vapeurs  
du solvant pour produire du phosgéne (gas fortement toxique)  
ou autres produits irritants.  
e. Ne jamais toucher simultanément les parties sous tension  
des porte-électrodes connectés à deux machines à souder  
parce que la tension entre les deux pinces peut être le  
total de la tension à vide des deux machines.  
f. Si on utilise la machine à souder comme une source de  
courant pour soudage semi-automatique, ces precautions  
pour le porte-électrode s’applicuent aussi au pistolet de  
soudage.  
11. Pour obtenir de plus amples renseignements sur la sûreté,  
voir le code “Code for safety in welding and cutting” CSA  
Standard W 117.2-1974.  
2. Dans le cas de travail au dessus du niveau du sol, se protéger  
contre les chutes dans le cas ou on recoit un choc. Ne jamais  
enrouler le câble-électrode autour de n’importe quelle partie  
du corps.  
PRÉCAUTIONS DE SÛRETÉ POUR  
LES MACHINES À SOUDER À  
TRANSFORMATEUR ET À  
REDRESSEUR  
3. Un coup d’arc peut être plus sévère qu’un coup de soliel,  
donc:  
a. Utiliser un bon masque avec un verre filtrant approprié  
ainsi qu’un verre blanc afin de se protéger les yeux du ray-  
onnement de l’arc et des projections quand on soude ou  
quand on regarde l’arc.  
1. Relier à la terre le chassis du poste conformement au code de  
l’électricité et aux recommendations du fabricant. Le dispositif  
de montage ou la piece à souder doit être branché à une  
bonne mise à la terre.  
b. Porter des vêtements convenables afin de protéger la  
peau de soudeur et des aides contre le rayonnement de  
l‘arc.  
c. Protéger l’autre personnel travaillant à proximité au  
soudage à l’aide d’écrans appropriés et non-inflammables.  
2. Autant que possible, I’installation et l’entretien du poste seront  
effectués par un électricien qualifié.  
4. Des gouttes de laitier en fusion sont émises de l’arc de  
soudage. Se protéger avec des vêtements de protection libres  
de l’huile, tels que les gants en cuir, chemise épaisse, pan-  
talons sans revers, et chaussures montantes.  
3. Avant de faires des travaux à l’interieur de poste, la debranch-  
er à l’interrupteur à la boite de fusibles.  
4. Garder tous les couvercles et dispositifs de sûreté à leur  
place.  
POWER MIG 300  
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6
6
MASTER TABLE OF CONTENTS FOR ALL SECTIONS  
RETURN TO MAIN MENU  
Page  
Safety.................................................................................................................................................i-iv  
Installation.............................................................................................................................Section A  
Operation...............................................................................................................................Section B  
Accessories...........................................................................................................................Section C  
Maintenance..........................................................................................................................Section D  
Theory of Operation..............................................................................................................Section E  
Troubleshooting and Repair ................................................................................................Section F  
How to Use Troubleshooting Guide............................................................................................F-2  
Troubleshooting Guide................................................................................................................F-4  
Test Procedures........................................................................................................................F-14  
Replacement Procedures .........................................................................................................F-36  
Electrical Diagrams ..............................................................................................................Section G  
Parts Manual.....................................................................................................P409 & P202-C Series  
POWER MIG 300  
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A-1  
A-1  
TABLE OF CONTENTS  
- INSTALLATION SECTION -  
INSTALLATION......................................................................................................................Section A  
Technical Specifications .............................................................................................................A-2  
Safety Precautions......................................................................................................................A-3  
Input Supply Connection Diagram..............................................................................................A-4  
Gun and Cable Installation..........................................................................................................A-5  
POWER MIG 300  
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A-2  
A-2  
INSTALLATION  
TECHNICAL SPECIFICATIONS – POWER MIG 300  
INPUT – SINGLE PHASE ONLY  
Standard Voltage/Frequency  
Input Current @ 230Amp Rated Output Input Current @ 300 Amp Rated Output  
208/230/460/575/60 Hz  
48/43/22/17 Amps  
72/62/31/25 Amps  
RATED OUTPUT  
Input Voltage  
Duty Cycle  
40%  
Amps  
Volts at Rated Amperes  
32 Volts  
208  
300 Amps  
300 Amps  
230Amps  
230/460/575  
208/230/460/575  
60%  
100%  
32 Volts  
29 Volts  
OUTPUT  
Welding Current Range (Continuous) Maximum Open Circuit Voltage  
5 – 350 Amps 67 Volts  
Welding Voltage Range  
10-45 Volts  
RECOMMENDED INPUT WIRE AND FUSE SIZES - SINGLE PHASE  
Input Voltage/  
230Amps @  
300Amps @  
75°C Copper Wire  
Fuse  
or  
Frequency (Hz)  
29 Volts  
32 Volts  
AWG (IEC)  
Sizes (MM2)  
(100% Duty Cycle)  
(60% Duty Cycle)  
Breaker Size  
208/60*  
230/60  
460/60  
575/60  
48 A  
43 A  
22 A  
17 A  
72 A  
62 A  
31 A  
25 A  
6 (16 mm2)  
6 (16 mm2)  
10 (6 mm2)  
12 (2.5 mm2)  
90 A  
80 A  
50 A  
35 A  
NOTE: Use #10 AWG Grounding Wire  
*For 208V Input ONLY: The duty Cycle Rating at 300 Amps is 40%  
PHYSICAL DIMENSIONS  
Height  
Width  
Depth  
Weight  
31.79 in  
808 mm  
18.88 in  
480 mm  
38.78 in  
985 mm  
255 Ibs  
116 kg  
WIRE SPEED RANGE  
Wire Speed  
50 – 700 IPM (1.27 – 17.8 m/minute)  
POWER MIG 300  
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A-3  
A-3  
INSTALLATION  
ONLY QUALIFIED PERSONNEL SHOULD  
INSTALL, USE OR SERVICE THIS EQUIP-  
MENT.  
Read entire installation section before starting  
installation.  
SAFETY PRECAUTIONS  
UNCRATING THE POWER MIG 300  
WARNING  
Cut banding and lift off cardboard carton. Cut banding  
holding the machine to the skid. Remove foam and  
corrugated packing material. Untape accessories from  
Gas Bottle Platform. Unscrew the two wood screws  
(at the Gas Bottle Platform) holding the machine to  
the skid. Roll the machine off the skid assembly.  
ELECTRIC SHOCK can kill.  
• Do not touch electrically live  
parts or electrode with skin or  
wet clothing.  
• Insulate yourself from work and  
ground.  
LOCATION  
• Always wear dry insulating  
gloves.  
Locate the welder in a dry location where there is free  
circulation of clean air into the louvers in the back and  
out the front. A location that minimizes the amount of  
smoke and dirt drawn into the rear louvers reduces  
the chance of dirt accumulation that can block air pas-  
sages and cause overheating.  
• Do not use AC welder if your  
clothing, cloves or work area is  
damp or if working on, under or  
inside work piece.  
Use the following equipment:  
- Semiautomatic DC constant volt-  
age (wire) welder.  
INPUT POWER, GROUNDING AND  
CONNECTION DIAGRAMS  
- DC manual (stick) welder.  
- AC welder with reduced voltage  
control.  
• Do not operate with panels  
removed.  
• Disconnect input power before  
servicing.  
1. Before starting the installation, check with the local  
power company if there is any question about  
whether your power supply is adequate for the volt-  
age, amperes, phase, and frequency specified on  
the welder nameplate. Also be sure the planned  
installation will meet the U.S. National Electrical  
Code and local code requirements. This welder  
may be operated from a single phase line or from  
one phase of a two or three phase line.  
FUMES AND GASES can be  
dangerous.  
• Keep your head out of fumes.  
• Use ventilation or exhaust to  
remove fumes from breathing  
zone and general area.  
2. The POWER MIG 300 is supplied connected for  
230 Volt Input. If the welder is to be operated on  
another voltage, it must be reconnected according  
to the instructions in Figure A.1  
WELDING SPARKS can  
cause fire or explosion.  
• Keep flammable material away.  
• Do not weld on closed contain-  
ers.  
ARC RAYS can burn eyes  
and skin.  
• Wear eye, ear and body protec-  
tion.  
Observe all safety information through-  
out this manual.  
-----------------------------------------------------------  
POWER MIG 300  
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A-4  
A-4  
INSTALLATION  
FIGURE A.1 — Triple Voltage Machine Input Connections  
3. The POWER MIG is shipped with a 10ft.(3.05m)  
input cable and plug connected to the welder.  
Using the instructions in Figure A.2, have a quali-  
fied electrician connect the receptacle or cable to  
the input power lines and the system ground per  
the U.S. National Electrical Code and any applica-  
ble local codes. See “Technical Specifications”  
at the beginning of this chapter for proper wire  
sizes. For long runs over 100ft. (30.48m), larger  
copper wires should be used. Fuse the two hot  
lines with super lag type fuses as shown in the fol-  
lowing diagram. The center contact in the recepta-  
cle is for the grounding connection. A green wire in  
the input cable connects this contact to the frame of  
the welder. This ensures proper grounding of the  
welder frame when the welder plug is inserted into  
the receptacle.  
FIGURE A.2 — Receptacle Diagram  
CONNECT TO A SYSTEM  
GROUNDING WIRE. SEE  
THE UNITED STATES  
NATIONAL ELECTRICAL  
CODE AND/OR LOCAL  
CODES FOR OTHER  
DETAILS AND MEANS FOR  
PROPER GROUNDING.  
CONNECT TO HOT WIRES  
OF A THREE-WIRE, SINGLE  
PHASE SYSTEM OR TO ONE  
PHASE OF A TWO OR  
THREE PHASE SYSTEM.  
POWER MIG 300  
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A-5  
A-5  
INSTALLATION  
GUN & CABLE ASSEMBLY INSTALLED  
GUN AND CABLE INSTALLATION  
INTO THE POWER MIG  
A Magnum 300 gun and 15Ft.(4.6m) cable  
(12Ft.(3.7m) for Codes 11000 and below) are provid-  
ed with the POWER MIG 300. A Magnum cable liner  
for .035-.045" (0.9-1.2 mm) electrode and contact tips  
for .035” (0.9mm) and .045” (1.2mm) are included for  
15Ft..  
1. Unscrew knurled screw on the drive unit front end  
(inside wire feed compartment) until tip of screw no  
longer protrudes into gun opening as seen from  
front of machine.  
2. Insert the male end of gun cable into the female  
casting through opening in front panel. Make sure  
connector is fully inserted and tighten knurled  
screw.  
WARNING  
3. Connect the gun trigger connector from the gun  
and cable to the mating receptacle inside the com-  
partment located above the gun connection made  
in step 2 above. Make sure that the key ways are  
aligned, insert and tighten retaining ring.  
Turn the welder power switch off before installing  
gun and cable.  
LINER INSTALLATION AND TRIMMING  
INSTRUCTION (SEE FIGURE A.3)  
SHIELDING GAS  
1. Remove the gas nozzle.  
(For Gas Metal Arc Welding Processes)  
2. Remove the gas diffuser from the gun tube. If gas  
diffuser contains a small set screw, loosen the set  
screw.  
Customer must provide cylinder of appropriate type  
shielding gas for the process being used.  
3. Lay gun and cable out straight on a flat surface.  
Loosen set screw of the connector on the back end  
of the gun.  
A gas flow regulator, for CO2 or Argon blend gas, and  
an inlet gas hose are factory provided with the  
POWER MIG 300.  
4. Insert the untrimmed Liner into the back end of the  
gun.  
WARNING  
CYLINDER may explode if  
damaged.  
5. Seat Liner bushing into back of gun. Secure Liner  
by tightening set screw. Do not install the gas dif-  
fuser at this time.  
• Gas under pressure is explosive. Always  
keep gas cylinders in an upright position  
and always keep chained to undercarriage  
or stationary support. See American  
National Standard Z-49.1, “Safety in  
Welding and Cutting” published by the  
American Welding Society.  
6. Lay the cable straight and trim Liner to 9/16”.  
Remove burrs.  
7. Secure the gas diffuser into the tube.  
Install shielding gas supply as follows:  
1. Set gas cylinder on rear platform of POWER MIG  
300. Hook chain in place to secure cylinder to rear  
of welder.  
8. Tighten the set screw against the Liner.  
CAUTION  
This screw should only be gently tightened. Over  
tightening will split or collapse the liner and cause  
poor wire feeding.  
2. Remove the cylinder cap. Inspect the cylinder  
valves and regulator for damaged threads, dirt,  
dust, oil or grease. Remove dust and dirt with a  
clean cloth.  
------------------------------------------------------------------------  
FIGURE A.3  
FEEDR END  
CABLE HANDLE  
GUN HANDLE  
GUN TUBE  
INSULATION TUBE  
BRASS CABLE  
CONNECTOR  
9/16 (14.3mm)  
LINER TRIM  
LENGTH  
MOLDED GAS PLUG  
SET SCREW  
CLAMPING SCREW  
SET SCREW  
GAS DIFFUSER  
LINER ASSEMBLY (LINER BUSHING TO BE SEATED  
TIGHT AGIANST BRASS CABLE CONNECTOR)  
NOZZLE INSULATION  
GAS NOZZLE  
POWER MIG 300  
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A-6  
A-6  
INSTALLATION  
DO NOT ATTACH THE REGULATOR IF OIL,  
GREASE OR DAMAGE IS PRESENT! Inform your  
gas supplier of this condition. Oil or grease in the  
presence of high pressure oxygen is explosive.  
3. Stand to one side away from the outlet and open  
the cylinder valve for an instant. This blows away  
any dust or dirt which may have accumulated in the  
valve outlet.  
WARNING  
Be sure to keep your face away from the valve  
outlet when “cracking” the valve.  
4. Attach the flow regulator to the cylinder valve and  
tighten the union nut(s) securely with a wrench.  
NOTE: If connecting to 100% CO2 cylinder, insert  
regulator adapter between regulator and cylinder  
valve. If adapter is equipped with a plastic washer,  
be sure it is seated for connection to the CO2 cylin-  
der.  
5. Attach one end of the inlet gas hose to the outlet  
fitting of the flow regulator, the other end to the  
POWER MIG 300 rear fitting, and tighten the union  
nuts securely with a wrench.  
6. Before opening the cylinder valve, turn the regula-  
tor adjusting knob counterclockwise until the  
adjusting spring pressure is released.  
7. Standing to one side, open the cylinder valve slow-  
ly a fraction of a turn. When the cylinder pressure  
gauge pointer stops moving, open the valve fully.  
WARNING  
Never stand directly in front of or behind the flow  
regulator when opening the cylinder valve. Always  
stand to one side.  
------------------------------------------------------------------------  
8. The flow regulator is adjustable. Adjust it to the flow  
rate recommended for the procedure and process  
being used before making the weld.  
POWER MIG 300  
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B-1  
B-1  
TABLE OF CONTENTS  
- OPERATION SECTION -  
Operation...............................................................................................................................Section B  
Definitions of Welding Modes.....................................................................................................B-2  
Product Description....................................................................................................................B-3  
Controls and Settings..........................................................................................................B-3/B-4  
Setting and Configuring..............................................................................................................B-5  
Multi-Process Panel Functions...................................................................................................B-6  
Arc Control..................................................................................................................................B-7  
Wire Drive Roll ............................................................................................................................B-8  
Changing Drive and Idle Roll Sets ..............................................................................................B-9  
Feeding Wire Electrode.............................................................................................................B-10  
Pulse Welding ...........................................................................................................................B-11  
Pulse-On-Pulse.........................................................................................................................B-12  
Power Mode..............................................................................................................................B-13  
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B-2  
B-2  
OPERATION  
Read entire Operation section before  
operating the POWER MIG 300.  
COMMON WELDING ABBREVIA-  
TIONS  
WARNING  
ELECTRIC SHOCK can kill.  
WFS  
• Wire Feed Speed  
• Do not touch electrically live  
parts or electrode with skin or  
wet clothing. Insulate yourself  
from work and ground.  
CC  
Constant Current  
CV  
• Always wear dry insulating  
gloves.  
Constant Voltage  
GMAW (MIG)  
• Gas Metal Arc welding  
FUMES AND GASES can be  
dangerous.  
• Keep your head out of fumes.  
GMAW-P (MIG)  
Gas Metal Arc welding-(Pulse)  
• Use ventilation or exhaust to  
remove fumes from breathing  
zone.  
GMAW-PP (MIG)  
• Gas Metal Arc welding-(Pulse-on-Pulse)  
WELDING SPARKS can  
cause fire or explosion.  
GTAW (TIG)  
Gas Tungsten Arc welding  
• Keep flammable material away.  
SMAW (STICK)  
Shielded Metal Arc welding  
• Do not weld on closed contain-  
ers.  
FCAW (INNERSHIELD)  
Flux Core Arc Welding  
ARC RAYS can burn eyes  
and skin.  
• Wear eye, ear and body protec-  
tion.  
Observe all safety information throughout  
this manual.  
DEFINITIONS OF WELDING MODES  
NON-SYNERGIC WELDING MODES  
A Non-synergic welding mode requires all welding  
process variables to be set by the operator.  
SYNERGIC WELDING MODES  
A Synergic welding mode offers the simplicity of  
single knob control. The machine will select the cor-  
rect voltage and amperage based on the wire feed  
speed (WFS) set by the operator.  
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B-3  
B-3  
OPERATION  
Other features  
PRODUCT DESCRIPTION  
Optional kits are available for push-pull welding, spool  
gun operation, push feeding of 3/64 aluminum with the  
standard POWER MIG 300 gun and wire feeder. A  
Dual Cylinder Mounting Kit is also offered.  
The POWER MIG 300 is a complete semiautomatic  
multi-process DC arc welding machine offering CV  
and CC DC welding. It is rated for 300 amps, 32 volts  
at a 60% duty cycle. The standard machine is  
equipped to weld CC-Stick, CC-GTAW, CV-FCAW,  
and synergic and non-synergic CV-GMAW / GMAW-P  
and Pulse-on-Pulse and Power Mode welding  
processes. See the descriptions for Pulse on  
Pulse™and Power Mode welding processes later in  
this section.  
CONTROLS AND SETTINGS  
(See Figure B.1)  
1. WIRE FEED SPEED (WFS) / AMP METER - This  
meter displays either the WFS or current value  
(Amps) depending on the status of the machine.  
Located below the display is the text "WFS" and  
"Amps." An LED light is illuminated to the left of one  
of these units to indicate the units of the value dis-  
played on the meter.  
Mode #5 and mode #6 are non-synergic CV GMAW  
modes for bare and flux cored wires, respectively. In  
these modes, the user presets the wire feed speed  
(WFS) on the left meter and the welding voltage on  
the right. These two settings are independent; that is,  
if the WFS is changed the voltage will remain con-  
stant, or vice versa.  
• Prior to CV operation, the meter displays the  
desired preset WFS value.  
• Prior to CC-Stick and CC-GTAW operation, the  
meter displays the preset current value.  
• During Welding, the meter displays actual average  
amps.  
• After welding, the meter holds the actual current  
value for 5 seconds. During this time, the display  
is blinking to indicate that the machine is in the  
"Hold" period. Output adjustment while in the  
"Hold" period results in the "prior to operation"  
characteristics stated above.  
• After the 5 second "Hold" period, the meter dis-  
plays the set WFS (CV modes) or Amp (CC  
modes) value.  
All of the other mode numbers designated as "CV" are  
synergic. Again, WFS is shown on the left meter and  
voltage is shown on the right meter. However, in using  
these modes, the WFS is preset and the voltage is  
preset only once. Now, when the WFS is changed, the  
voltage will change with it, so that the arc appearance  
and arc length will stay the same without the necessity  
to re-adjust the voltage.  
The modes shown as "GMAW-P" or " GMAW-PP" are  
all synergic pulsed modes. In these modes WFS is  
shown on the left meter and "Trim" is shown on the  
right meter. The user adjusts WFS to obtain an arc  
with the correct arc energy for the material thickness  
being welded. The Trim, which is adjustable from val-  
ues of –1.5 to 0 (OFF) and up to +1.5 controls the arc  
length. Higher values of Trim give longer arc lengths.  
Once the user has adjusted the Trim for one WFS, the  
power supply will synergically change many variables  
so that, as the WFS is changed, the arc length and  
arc appearance will remain the same. The synergic  
modes are usable with both push and push – pull  
torches, as described later in this Manual. When using  
a spool gun, however, although the synergic pulsed  
modes are still accessible, they must be used in a  
non-synergic manner as described in the Accessory  
Section.  
FIGURE B.1  
The digital microcomputer based control system  
allows easy and accurate adjustment of weld parame-  
ters through the multi-process panel located on the  
front of the machine. The POWER MIG 300 is  
equipped with a 6-pin and 7-pin connector to allow  
operation of a push-pull gun for feeding aluminum  
wires, a spool gun, remotes, and a foot amptrol.  
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B-4  
B-4  
OPERATIONS  
5. MULTI-PROCESS PANEL - This panel enables selection  
of weld modes as well as adjustment of certain weld  
parameters within each weld mode.  
2. VOLT / TRIM METER - This meter displays either  
the voltage or trim value depending on the status of  
the machine. Located below the display is the text  
"Volts" and "Trim." An LED light is illuminated to  
the left of one of these in order to indicate the units  
of the value displayed in the meter.  
The eight discrete LED’s are used to identify which selec-  
tion will be shown on the display. The possible selections  
are:  
CV Processes  
• Weld Mode (Process selection choices)  
• Preflow / Postflow  
• Prior to GMAW and FCAW operation, the meter  
displays the desired preset Voltage value.  
• Prior to synergic GMAW-P and GMAW-PP oper-  
ation, the meter displays the desired preset Trim  
value. Trim adjusts the synergic default voltage  
as a percentage of that voltage. A trim value of 1  
is the default and results in the recommended  
voltage setting for a given wire feed speed.  
Adjusting trim to a value of .95, adjusts the volt-  
age to 95% of the recommended voltage.  
• During Welding, the meter displays actual aver-  
age volts.  
• After welding, the meter holds the actual voltage  
value for 5 seconds. During this time , the display  
is blinking to indicate that the machine is in the  
"Hold" period. Output adjustment while in the  
"Hold" period results in the "prior to operation"  
characteristics stated above.  
• Run-In  
• Start  
• Arc Control  
• Crater  
• Burnback  
• Spot  
Choice of weld parameters  
that can be adjusted.  
Complete descriptions of  
each parameter are found  
}
later in this section.  
Only one LED will be illuminated at any time. The Weld  
Mode attribute will always be a valid selection (the other  
attributes may not be available in all processes).  
5A. SELECT Toggle Switch  
• This switch toggles through the 8 selections detailed  
above the switch.  
• A red LED is located next to each possible selection  
and is illuminated when that choice can be changed.  
5B. Display Meter  
• This meter displays the active weld mode (a set of  
weld parameters that have been determined to pro-  
vide the recommended results for a particular welding  
process) when the “Weld Mode” LED is illuminated or  
when any one of the other seven LED’s is illuminated  
the meter indicates what value that welding parame-  
ter has been set to.  
• After the 5 second "Hold" period, the meter dis-  
plays the set Voltage (GMAW, FCAW) or Trim  
(GMAW-P) value.  
CC Processes  
• The meter displays the status of the output.  
5C. SET Toggle Switch  
• This switch adjusts (up or down) the value shown on  
the display meter. When the WELD MODE LED is illu-  
minated, this switch is changing the weld mode of the  
machine. The most commonly used modes are dis-  
played in the chart on the right half of the Multi-  
Process Panel.  
• When output is enabled, the meter will display "ON."  
• When there is no output, the meter will display "OFF."  
3. OUTPUT CONTROLS - The POWER MIG 300 has 2  
encoder knobs to adjust weld parameters.  
If the LED next to  
a
weld parameter  
• Each encoder changes the displayed value of the meter  
located directly above that encoder.  
(Preflow/Postflow, Run-In, Start, etc.) is illuminated,  
the SET switch will adjust the setting of that specific  
weld parameter. The setting is shown on the display  
meter.  
• In CC-GTAW modes, the left encoder sets the maxi-  
mum welding current. Full depression of a foot or hand  
amptrol results in the preset level of current.  
6. ON/OFF POWER SWITCH  
• In CC-Stick and CC-GTAW, the right encoder activates  
and de-activates the output. Turning the encoder clock-  
wise enables the output if not using a remote trigger  
device. To de-energize the output, turn the encoder  
counter-clockwise. The display above will indicate the  
"ON" or "OFF" status of the output.  
4. THERMAL - This status light illuminates when the power  
source has been driven into thermal overload.  
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B-5  
B-5  
OPERATION  
SETTING AND CONFIGURING THE POWER  
MIG 300 FOR WELDING  
• Check that the electrode polarity is correct for the process  
and turn the Power Switch to the "ON" position. After the  
"boot-up" period (approximately 20 seconds), the POWER  
MIG 300 will default to the last preset weld mode that was  
active when the machine was powered down. The Multi-  
Process Panel defaults with the "Weld Mode" active.  
• Toggle the SET switch to the desired "Weld Mode" opera-  
tion. The Multi-Process Meter displays a weld mode num-  
ber corresponding to a CC or CV welding process as  
detailed by the chart on the right side of the panel. In the  
example shown in Figure B.2 “3” is displayed above the  
SET switch. This means that the machine is set for CC-  
GTAW (TIG) welding.  
• Toggle the SELECT switch to activate the "weld parame-  
ters" for the selected weld mode.  
• Set each parameter using the SET switch to adjust the  
parameter displayed on the display meter.  
NOTE: If the LED next to the weld parameter is flashing, the  
WFS/AMP and/or the Volt/Trim values can also be adjusted  
for that parameter using the control knobs below each dis-  
play meter. An LED below each of the displays will also be  
flashing to indicate which value is adjustable.  
The Table B.1 shows which weld parameters are adjustable  
for a given weld mode. The weld parameters are detailed  
later in this section.  
FIGURE B.2  
3
TABLE B.1  
PREFLOW /  
POSTFLOW  
-----  
RUN IN START ARC CONTROL  
CRATER  
BURNBACK  
SPOT  
CC-STICK  
CC-GTAW  
CV-FCAW  
CV-GMAW  
CV-GMAW-P  
POWER  
-----  
-----  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
-----  
Yes  
Yes  
Yes  
Yes  
-----  
-----  
Yes  
Yes  
Yes  
Yes  
-----  
-----  
Yes  
Yes  
Yes  
Yes  
-----  
-----  
Yes  
Yes  
Yes  
Yes  
Yes  
-----  
Yes  
Yes  
Yes  
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B-6  
B-6  
OPERATION  
Run-In  
MULTI-PROCESS PANEL FUNCTIONS  
• The Run-In function offers the ability to set a wire feed  
speed, from trigger until an arc is established, that is inde-  
pendent of the Welding or Start wire feed speed. Setting a  
Run-In WFS lower than the welding WFS avoids stubbing  
problems when starting the arc.  
Weld Mode  
Setting the Weld Mode is selecting the proper program  
from the ones available in the machine’s memory for a  
particular welding application. The table on the right side  
of the front panel (See Figure B.2) gives information on  
the different programs available in this machine. It  
describes the type of process (CV, CC, synergic  
GMAW), type of metal (mild steel, stainless steel, alu-  
minum), type of shielding gas and size of electrode rec-  
ommended for a particular mode.  
• Run-In is selected by toggling the SELECT switch until the  
LED next to RUN-IN is lit. A Run-In WFS may be adjusted  
using the SET switch on the Multi-Process Panel. The  
Display meter on the Multi-Process Panel will indicate the  
run-in speed. Do not use the Output Control Knob on the  
upper case front to adjust the WFS. This will change the  
welding WFS displayed in the meters on the upper case  
front.  
The Weld Mode selection is enabled by toggling the  
SELECT switch until the LED next to Weld Mode is lit. A  
Weld Mode number will be displayed on the display  
meter. Toggling the SET switch up or down will increase  
or decrease the WELD MODE number displayed. The  
machine will change to the selected weld mode after two  
seconds of SET switch inactivity. If the SELECT switch is  
changed before two seconds of SET switch inactivity, the  
machine will not change modes. The last active Weld  
Mode will be saved at power down so that it will be  
selected with the next power up of the machine.  
• The default value for Run-In is "OFF."  
• Run-In speed is adjustable from 50 ipm to 150 ipm  
(Inches per Minute).  
Start Procedure  
This machine provides the option of setting a Starting  
Procedure to start the weld, and from there, to ramp to the  
welding procedure over a specified amount of time.  
Typically starting on a higher starting procedure than the  
welding procedure is known as a “Hot Start”. Setting a start-  
ing procedure lower than the welding procedure is known as  
a “Cold Start”.  
Preflow / Postflow  
• The Preflow setting allows a time to be selected for  
shielding gas to flow after the trigger is pulled and prior  
to wire feeding and establishing an arc.  
For SMAW (Stick) welding setting a “Hot Start” helps to  
minimize stubbing the electrode.  
• The Postflow setting allows a time to be selected for  
shielding gas to continue to flow after the trigger is  
released and output current is turned off.  
For GTAW (TIG) welding setting a “Cold Start” minimizes  
burn-through of thin materials when not using a manual  
amperage control.  
• The Preflow timer will be selected by toggling the  
SELECT switch until the LED next to PREFLOW  
/POSTFLOW is lit. The display meter will read Pre. The  
present Preflow time will be displayed and can be  
changed by positioning the SET switch up or down.  
For Wire Feed welding using a start procedure can help  
improve starting characteristics. A good example is when  
welding aluminum. Aluminum’s high thermal conductivity  
results in heat spreading around the plate very fast.  
Therefore more energy is necessary at the very beginning to  
heat up the starting point of the weld. Once the welding  
begins, it is not necessary to give this extra heat anymore  
so a ramp down to the welding procedure is necessary.  
• The Postflow timer will be selected by pressing down  
the SELECT switch an additional time. The LED next  
to PREFLOW / POSTFLOW will remain lit; but the dis-  
play meter will now read Pos. The present Postflow  
time will be displayed and can be changed by position-  
ing the SET switch up or down.  
To set a Start Procedure begin by using the SELECT switch  
to select the Start LED. Using the SET switch, enter the  
desired Start ramp time duration (its available values range  
from 0.01 seconds to 0.50 seconds in increments of 0.01  
seconds or the default value of OFF). This value will be dis-  
played on the digital meter of the multiprocess panel (See  
Figure B.2).  
• The default value for both Preflow and Postflow is  
"OFF" (0 seconds).  
• Preflow can be adjusted from 0 to 2.5 seconds in 0.1  
second increments.  
• Postflow can be adjusted from 0 to 10.0 seconds in 0.1  
second increments.  
After setting the Start time also set the WFS, and  
voltage/trim. The way to know what information needs  
to be entered is to look for flashing LED’s. If an LED is  
flashing that parameter value needs to be entered.  
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B-7  
B-7  
OPERATION  
Carbon steel electrodes employed in GMAW-S usually per-  
form best when the droplet size is regulated by pinch to  
reduce the droplet size transferred with each short-circuit  
event.  
Arc Control (See Table B.2)  
There are no specific unit values offered because the setting  
of this feature largely depends upon operator preference.  
Arc Control has a different effect on the character of the arc  
depending upon the welding process applied.  
When welding with solid stainless steel types of electrodes it  
is usually desirable to increase the energy delivered to the  
arc. High percentage argon blends with a 2 % addition of  
oxygen or a three part shielding gas blend comprised of  
90% Helium + 7.5% Argon + 2.5 % carbon dioxide are usu-  
ally employed. The added energy is associated, in this sce-  
nario, with increasing the inductance (negative numeric val-  
ues). By adding to the energy level the weld bead appear-  
ance improves – spatter levels decrease and wetting action  
at the toes of a fillet weld increases. The arc is softer with  
the higher inductance setting and the arc lends itself to  
faster travel speed.  
In SMAW (STICK mode), arc control adjusts the arc force. It  
can be set to the lower range for a soft and less penetrating  
arc characteristic (negative numeric values) or to the higher  
range (positive numeric values) for a crisp and more pene-  
trating arc. Normally, when welding with cellulosic types of  
electrodes (E6010, E7010, E6011), a higher energy arc is  
required to maintain arc stability. This is usually indicated  
when the electrode sticks to the work-piece or when the arc  
pops-out during manipulative technique. For low hydrogen  
types of electrodes (E7018, E8018, E9018, etc.) a softer arc  
is usually desirable and the lower end of the Arc Control  
suits these types of electrodes. In either case the arc con-  
trol is available to increase or decrease the energy level  
delivered to the arc.  
In GMAW-P, the pulsed spray mode of metal transfer, the  
Arc Control is, once again, used to increase and decrease  
the focus of the energy delivered to the arc. Increasing the  
setting in the range of +1 to +10 results in an increase in  
pulsed frequency, and the effect is to narrow the arc cone  
and concentrate the available energy to a smaller area.  
Decreasing the Arc Control setting from –1 to –10 results in  
a reduction of pulsed frequency – the result is a broader arc  
cone, which creates a wider weld bead.  
In GMAW-S, the short-circuiting mode of metal transfer, the  
Arc Control features the ability to increase or decrease the  
energy level at the arc. Setting the arc control from 1 to 10  
decreases energy, and setting the Arc Control from 0 to –10  
increases the energy delivered to the arc.  
Solid carbon steel electrodes in a range from .025"- .045" (.6  
mm – 1.1 mm) are nominally used, and the shielding gas  
blend for GMAW-S is usually 100% carbon dioxide or a  
blend of argon and carbon dioxide. The Arc Control in this  
scenario is set to control the droplet size and more pinch is  
added (increasing pinch reduces energy to the arc) to  
achieve the "bacon frying" sound associated with this mode  
of metal transfer.  
Important to note here is that if a component of a pulsed  
waveform is increased, then another must be decreased.  
Adding pulsed frequency through an increase in the Arc  
Control setting, then also results in a proportional decrease  
in background current. If this were not the case, then the arc  
would become too long, with too much energy, and the arc  
would be unusable.  
TABLE B.2-ARC CONTROL SETTINGS BY PROCESS  
PROCESS  
ARC  
SETTING  
APPLICATION AND  
RESULT  
CONTROL  
SYNONYM  
Arc Force  
SMAW (STICK)  
Lower (-1 to -10) for  
low hydrogen types of  
electrodes. Higher (+1  
to +10) for cellulosic  
and other types.  
Minus settings are soft  
and buttery for low  
hydrogen electrodes.  
Plus settings are harsh  
and digging for other  
types of electrodes.  
The minus settings  
result a more fluid  
GMAW – S (Short  
circuiting metal  
transfer  
Inductance or  
Pinch Control  
Setting -1 to -10 for  
softer higher energy  
arc. Setting +1 to +10  
for a crisper lower  
energy arc.  
puddle and larger  
droplet size. The lower  
settings reduce the  
droplet size and reduce  
energy to the arc.  
GMAW – P (Pulsed  
spray metal transfer)  
Pulsed frequency  
control  
Minus settings reduces  
frequency. Plus  
settings increase  
frequency.  
Wider arc cone and  
weld bead. Narrower  
arc cone and narrower  
weld bead.  
Pulse – on –Pulse™ Pulsed frequency  
(Aluminum Only) array control  
Minus settings result in  
lower array frequency  
and the plus settings  
increase the array  
frequency.  
Minus settings result in  
a wider bead with more  
distinct ripples. Plus  
settings narrow the  
resultant bead and the  
ripples are less distinct.  
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B-8  
B-8  
OPERATION  
In the case of special waveforms designed for pulsed weld-  
ing aluminum, Pulse on Pulse, the effect is similar to what  
occurs with standard pulse. As the Arc Control is increased  
from +1 to +10 the frequency of the Pulse on Pulse array  
increases. As the frequency increases the weld bead ripples  
become less distinct and the arc cone narrows. When the  
Arc Control is set from -1 to -10 the Pulse on Pulse arrays  
decrease in frequency, the weld bead ripples become more  
distinct, and the bead width increases.  
• In the GMAW, FCAW, and Power weld modes, crater  
WFS and voltage are adjustable using the control knobs  
on the upper case front. This in indicated by the flashing  
LED’s next to "WFS" and "VOLTS."  
• In the GMAW-P weld modes, Crater WFS and trim are  
adjustable. This is indicated by the flashing LEDs next to  
"WFS" and "TRIM."  
In GMAW-PP mode, arc control adjusts the modulation fre-  
Burnback  
quency, which means the speed at which the ripples are  
produced in the weld. (See Pulse-on-Pulse description later  
in this section.) When faster travel speeds are desired, arc  
control needs to be set higher. When slower travel speeds  
are desired, arc control needs to be set lower.  
Setting the Burnback means setting the adjustable time  
delay between turning off the wire feeding and turning off  
the arc. Burnback helps to prevent wire sticking to the pud-  
dle.  
• The Burnback feature will allow current to continue to flow  
for a specified time period at the end of a weld after wire  
feeding has stopped.  
• The Arc-control adjustment is selected by toggling the  
SELECT switch until the LED next to ARC CONTROL is  
lit. The Arc-control value will be displayed. Arc-control can  
be adjusted by toggling the SET switch up or down.  
• The default value is "OFF."  
• The Burnback timer will be selected by toggling the  
SELECT switch until the LED next to BURNBACK is lit. A  
burnback time may be set using the SET switch.  
Crater  
The crater is the end of the weld, which normally solidifies  
creating a concave surface. This can result in stresses that  
can cause cracks in the center of the crater. The purpose of  
the Crater control is to fill up the crater, so that its surface  
becomes flat.  
• The default value is "OFF" (0 seconds).  
• Burnback time is adjustable from 0 to 0.25 seconds in  
0.01 second increments.  
Spot  
Crater control in this machine is more efficient than in other  
machines. Normally, in other machines, the crater filling pro-  
cedure is a step down from the welding WFS to the crater  
filling WFS. In this machine instead of a step down, the tran-  
sition is a ramp down, which results in a more controlled fill-  
ing up of the crater and so, less stresses present in it.  
The Spot Timer adjusts arc on-time for spot or tack welds.  
• With the Spot feature active (Spot time selected), when  
the trigger is pulled and the arc is established, the weld  
will continue until the expiration of the spot timer and the  
next active state will be enabled (crater or burnback). The  
trigger must be released and pulled again for another Spot  
cycle.  
The values to enter are first the desired time to stay at the  
Crater settings and the desired WFS and voltage/trim to fill  
the crater.  
• The Spot timer is selected by toggling the SELECT switch  
until the LED next to SPOT is lit. The present SPOT time  
will be displayed and can be changed by toggling the SET  
switch up or down.  
• The Crater timer is selected by toggling the SELECT  
switch until the LED next to CRATER is lit and flashing. A  
crater time may be set using the SET switch.  
• The default value is "OFF" (0 seconds).  
• The available values for crater control time go from "Off"  
to 0.1 seconds and from there to 10.0 seconds in incre-  
ments of 0.1 seconds.  
• Spot can be adjusted from 0 to 10.0 seconds in 0.1 sec-  
ond increments.  
• The Crater function offers the ability to set an endpoint for  
WFS and Voltage that will be reached over a specified  
time period. At the end of the weld when the trigger is  
released, the crater timer will begin and the WFS and  
Volts settings will ramp down from the Weld Mode WFS  
and Voltage settings to the Crater WFS and Voltage set-  
tings over the time selected. This creates a ramp down of  
the WFS and Volts during the Crater time.  
WIRE DRIVE ROLL  
The drive rolls installed with the POWER MIG 300 have two  
grooves, one side for .030" (0.8mm) solid steel electrode,  
and the other for the .045”(1.2mm) electrode. The actual  
drive roll size is stenciled on the side opposite of its groove.  
If feeding problems occur, a check may be required to make  
sure that the wire size and the drive roll size matches. See  
"Procedure for Changing Drive Rolls" in this section.  
POWER MIG 300  
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OPERATION  
B-9  
B-9  
5. Rotate the spindle and adapter so the retaining  
spring is at the 12 o'clock position.  
PROCEDURE FOR CHANGING  
DRIVE AND IDLE ROLL SETS  
6. Position the Readi-Reel so that it will rotate in a direc-  
tion when feeding so as to be de-reeled from top the  
of the coil.  
1. Turn off the power source.  
2. Release the pressure on the idle roll by swinging  
the adjustable pressure arm down toward the back  
of the machine. Lift the cast idle roll assembly and  
allow it to sit in an upright position.  
7. Set one of the Readi-Reel inside cage wires on the  
slot in the retaining spring tab.  
3. Remove the outside wire guide retaining plate by  
loosening the two large knurled screws.  
8. Lower the Readi-Reel to depress the retaining spring  
and align the other inside cage wires with the grooves  
in the molded adapter.  
4. Twist the drive roll retaining mechanism to the  
unlocked position as shown below and remove the  
drive roll. (See Figure B.3)  
9. Slide cage all the way onto the adapter until the  
retaining spring "pops up" fully.  
FIGURE B.3  
CAUTION  
Check to be sure the retaining ring has fully returned to the locking  
position and has securely locked the Readi-Reel cage in place.  
Retaining spring must rest on the cage, not the welding electrode.  
-----------------------------------------------------------------------------------------------  
10. To remove Readi-Reel from Adapter, depress retain-  
ing spring tab with thumb while pulling the Readi-  
Reel cage from the molded adapter with both hands.  
Do not remove adapter from spindle.  
LOCKED POSITION  
UNLOCKED POSITION  
5. Remove the inside wire guide plate.  
6. Replace the drive and idle rolls and inside wire  
guide with a set marked for the new wire size.  
NOTE: Be sure that the gun liner and contact tip  
are also sized to match the selected wire size.  
FIGURE B.4  
7. Manually feed the wire from the wire reel, over the  
drive roll groove and through the wire guide and  
then into the brass bushing of the gun and cable  
assembly.  
8. Replace the outside wire guide retaining plate by  
tightening the two large knurled screws. Reposition  
the adjustable pressure arm to its original position  
to apply pressure. Adjust pressure as necessary.  
TO MOUNT 10 to 44 Lb. (4.5-20 kg) SPOOLS (12"/300  
mm Diameter) or 14Lb.(6 Kg) Innershield Coils:  
WIRE REEL LOADING - READI-REELS,  
SPOOLS OR COILS  
(For 13-14 lb. (6 Kg) Innershield coils, a K435 Coil  
Adapter must be used).  
To Mount a 30 Lb. (14 kg) Readi-Reel Package  
(Using the Molded Plastic K363-P Readi-Reel  
Adapter):  
1. Open the Wire Drive Compartment Door  
1
. Open the Wire Drive Compartment Door  
2. Depress the Release Bar on the Retaining Collar  
and remove it from the spindle.  
2. Depress the Release Bar on the Retaining Collar  
and remove it from the spindle.  
3. Place the spool on the spindle making certain the  
spindle brake pin enters one of the holes in the  
back side of the spool (Note: an arrow mark on the  
spindle lines up with the brake holding pin to assist  
in lining up a hole). Be certain the wire comes off  
the reel in a direction so as to de-reel from the top  
of the coil.  
3. Place the Optional Adapter on the spindle  
4. Re-install the Retaining Collar. Make sure that the  
Release Bar “pops up” and that the collar retainers  
fully engage the retaining ring groove on the spin-  
dle.  
POWER MIG 300  
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B-10  
B-10  
OPERATION  
4. Re-install the Retaining Collar. Make sure that the  
Release Bar “pops up” and that the collar retainers  
fully engage the retaining ring groove on the spin-  
dle.  
1. Press end of gun against a solid object that is elec-  
trically isolated from the welder output and press  
the gun trigger for several seconds.  
2. If the wire “birdnests”, jams or breaks at the drive  
roll, the idle roll pressure is too great. Back the  
adjustment knob out 1/2 turn, run new wire through  
gun, and repeat above steps.  
FEEDING WIRE ELECTRODE  
WARNING  
When triggered, the electrode and drive mecha-  
nism are electrically “hot” relative to work and  
ground and remain “hot” several seconds after  
the gun trigger is released.  
3. If the only result was drive roll slippage, loosen the  
adjustment knob on the conductor plate and pull  
the gun cable forward about 6" (15 cm). There  
should be a slight waviness in the expose wire. If  
there is not waviness, the pressure is too low.  
Tighten the adjustment knob 1/4 turn, reinstall the  
gun cable and repeat the above steps.  
------------------------------------------------------------------------  
NOTE: Check that drive rolls, guide plates and gun  
parts are proper for the wire size and type being used.  
Refer to Table C.1 in ACCESSORIES section.  
AVOIDING WIRE FEEDING  
PROBLEMS  
1. Turn the Readi-Reel or spool until the free end of  
the electrode is accessible.  
Wire feeding problems can be avoided by observing  
the following gun handling procedures:  
2. While securely holding the electrode, cut off the  
bent end and straighten the first six inches. (If the  
electrode is not properly straightened, it may not  
feed properly through the wire drive system).  
a. Do not kink or pull cable around sharp corners.  
b. Keep the gun cable as straight as possible when  
welding or loading electrode through cable.  
3. Release the pressure on the idle roll by swinging  
the adjustable pressure arm down toward the back  
of the machine. Lift the cast idle roll assembly and  
allow it to sit in an upright position. Leave the outer  
wire guide plate installed. Manually feed the wire  
through the incoming guide bushing and through  
the guide plates (over the drive roll groove). Push a  
sufficient wire length to assure that the wire has fed  
into the gun and cable assembly without restriction.  
Reposition the adjustable pressure arm to its origi-  
nal position to apply pressure to the wire.  
c. Do not allow dolly wheels or trucks to run over  
cables.  
d. Keep cable clean by following maintenance instruc-  
tions.  
e. Use only clean, rust-free electrode. Lincoln elec-  
trodes have proper surface lubrication.  
f. Replace the contact tip when the arc starts to  
become unstable or the contact tip end is fused or  
deformed.  
4. Press gun trigger to feed the electrode wire through  
the gun.  
g. Keep wire reel spindle brake tension to the mini-  
mum required to prevent excess reel over-travel  
which may cause wire “loop-offs” from the coil.  
IDLE ROLL PRESSURE SETTING  
The idle roll pressure adjustment knob is set at the  
factory at the #2 hash mark. This is an approximate  
setting. The optimum idle roll pressure varies with  
type of wire, wire diameter, surface conditions, lubri-  
cation, and hardness. As a general rule, hard wires  
may require greater pressure, and soft, or aluminum  
wire, may require less pressure than the factory set-  
ting. The optimum idle roll setting can be determined  
as follows:  
h. Use proper drive rolls and wire drive/idle roll pres-  
sure for wire size and type being used.  
POWER MIG 300  
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B-11  
B-11  
OPERATION  
Pulsed MIG is an advanced form of welding that takes  
the best of all the other forms of transfer while minimiz-  
ing or eliminating their disadvantages. Unlike short cir-  
cuit, pulsed MIG does not create spatter or run the risk  
of cold lapping. The welding positions in pulsed MIG  
are not limited as they are with globular or spray and its  
wire use is definitely more efficient. Unlike the spray arc  
process, pulsing offers controlled heat input that allows  
better welding on thin materials, lower wire feed speeds  
and leads to less distortion and improved overall quality  
and appearance. This is especially important with stain-  
less, nickel and other alloys that are sensitive to heat  
input.  
SPECIAL WELDING PROCESSES  
AVAILABLE ON THE POWER MIG 300  
PULSE WELDING (GMAW-P)  
The pulsed-arc process is, by definition, a spray trans-  
fer process wherein spray transfer occurs in pulses at  
regularly spaced intervals. In the time between pulses,  
the welding current is reduced and no metal transfer  
occurs.  
Pulsed-arc transfer is obtained by operating a power  
source between low and high current levels. The high  
current level or “pulse” forces an electrode drop to the  
workpiece. The low current level or “background”  
maintains the arc between pulses. (See Figure B.5).  
In GMAW-P mode, arc control adjusts the background  
current and frequency of the wave. When arc control  
goes up, the frequency increases thus increasing the  
droplet transfer rate.  
FIGURE B.5  
EACH PULSE DELIVERS ONE DROPLET OF WELD MATERIAL  
FREQUENCY  
SPRAY TRANSITION  
CURRENT  
POWER MIG 300  
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B-12  
B-12  
OPERATION  
When Arc Control is used in the Pulse on Pulse  
modes, it does the same things it does in the other  
pulsed modes: decreasing the Arc Control decreases  
the droplet transfer and weld deposition rate.  
Increasing the Arc Control increases the droplet trans-  
fer and weld deposition rate. Since Arc Control varies  
weld droplet transfer rate, the Arc Control can be used  
to vary the ripple spacing in the weld bead.  
PULSE-ON-PULSE™ (GMAW-PP)  
Pulse on Pulse™ is a Lincoln process specifically  
designed for use in welding relatively thin (less than  
1/4" thick) aluminum (See Table B.3). It gives weld  
beads with very consistent uniform ripple.  
In Pulse on Pulse modes, two distinct pulse types are  
used, instead of the single pulse type normally used in  
GMAW-P. A number of high energy pulses are used  
to obtain spray transfer and transfer metal across the  
arc. Such pulses are shown in Figure B.6. After a  
number "N" of such pulses, depending on the wire  
feed speed used, an identical number "N" of low ener-  
gy pulses are performed. These low energy pulses,  
shown in Figure B.6, do not transfer any filler metal  
across the arc and help to cool the arc and keep the  
heat input low.  
BENEFITS OF PULSE ON PULSE FROM  
LINCOLN ELECTRIC  
• Excellent appearance of the weld bead  
• Improved cleaning action  
• Reduced porosity  
FIGURE B.6  
Table B.3 shows WFS and Trim settings for common  
aluminum types and wire sizes when welding with  
Pulse-on-Pulse. The welds made to obtain the values  
in the table were fillet welds in the flat position. The  
values in the table can be helpful as a starting point to  
establish a welding procedure. From there, adjust-  
ments need to be made to set the proper procedure  
for each specific application (out-of-position, other  
types of joints, etc.).  
"N" PULSES  
"N" PULSES  
HIGH HEAT  
PULSES  
LOW HEAT  
PULSES  
PEAK  
AMPS  
BACKGROUND  
AMPS  
TIME  
The Peak Current, Background Current, and  
Frequency are identical for the high energy and low  
energy pulses. In addition to cooling the weld down,  
the major effect of the low energy pulses is that they  
form a weld ripple. Since they occur at very regular  
time intervals, the weld bead obtained is very uniform  
with a very consistent ripple pattern. In fact, the bead  
has its best appearance if no oscillation of the welding  
gun ("whipping") is used.(See Figure B.7)  
The comments on Table B.3 show values of WFS  
below which it is not recommended to weld. The rea-  
son is, that below these values the weld transfer will  
change from a spray arc to a short-arc, which is not  
advisable when welding aluminum.  
FIGURE B.7  
WELDING PROCEDURES FOR PULSE-ON-PULSE (TABLE B.3)  
MATERIAL  
Aluminum 4043  
100% Ar.  
E4043  
Aluminum 4043  
100% Ar.  
E4043  
Aluminum 5356  
100% Ar.  
E5356  
Aluminum 5356  
100% Ar.  
E5356  
GAS  
WIRE  
WIRE SIZE  
WELD MODE  
0.035  
3/64  
0.035  
3/64  
98  
99  
101  
102  
14 ga.  
250 / 1.0  
200 / 1.0  
230 / 1.0  
225 / 1.0  
10 ga.  
3/16  
1/4  
400 /1.0  
550 / 1.0  
600 / 1.0  
280 / 1.0  
340 / 1.0  
400 / 1.0  
425 / 1.0  
670 / 1.0  
700 / 1.0  
400 / 1.0  
500 / 1.0  
550 / 0.9  
Not Recommended  
below 200 WFS  
Not Recommended  
below 100 WFS  
Not Recommended  
below 200 WFS  
Not Recommended  
below 200 WFS  
COMMENTS  
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B-13  
B-13  
OPERATION  
POWER MODE™  
Start by setting the wire feed speed based upon mate-  
rial thickness and appropriate travel speed. Then  
adjust the Volts/Trim knob as follows:  
The Power Mode™ process was developed by  
Lincoln to maintain a stable and smooth arc at low  
procedure settings which are needed to weld thin  
metal without pop-outs or burning-through. For  
Aluminum welding, it provides excellent control and  
the ability to maintain constant arc length. This results  
in improved welding performance in two primary types  
of applications.  
• For steel, listen for the traditional “frying egg”  
sound of a good short-arc MIG procedure to know  
you have the process set correctly.  
• For aluminum, simply adjust the Volts/Trim knob  
until the desired arc length is obtained.  
• Short Arc MIG at low procedure settings.  
• Aluminum MIG welding.  
Note the Volts/Trim display is simply a relative number  
and DOES NOT correspond to voltage.  
Power Mode™ is a method of high speed regulation  
of the output power whenever an arc is established. It  
provides a fast response to changes in the arc. The  
higher the Power Mode Setting, the longer the arc. If a  
welding procedure is not established, the best way to  
determine the Power Mode Setting is by experimenta-  
tion until the desired output result is established.  
Some procedure recommendations appear in Table  
B.4.  
In the Power Mode two variables need to be set:  
• Wire Feed Speed  
• Power Mode Trim  
Setting up a Power Mode procedure is similar to set-  
ting a CV MIG procedure. Select a shielding gas  
appropriate for a short arc process.  
• For steel, use 75/25 Ar/CO2 shield gas.  
• For Stainless, select a Helium blend Tri-Mix.  
• For Aluminum, use 100% Ar.  
RECOMMENDED WELDING PROCEDURES FOR POWER MODE - TABLE B.4  
MATERIAL  
WIRE  
Aluminum 4043 Aluminum 5356  
Mild Steel  
L56  
Mild Steel  
L56  
Mild Steel  
L56  
Mild Steel  
L56  
Mild Steel  
L56  
Mild Steel  
L56  
Stainless Steel Stainless Steel  
E4043  
0.035  
E5356  
0.035  
E308L  
0.030  
E308L  
0.035  
WIRE SIZE  
GAS  
0.025  
0.025  
0.030  
0.030  
0.035  
0.035  
100% Ar.  
100% Ar.  
100% CO2  
75/25 Ar/CO2  
100 / 0.8  
120 / 1.0  
140 / 1.5  
190 / 2.0  
260 / 3.0  
330 / 4.5  
100% CO2  
75/25 Ar/CO2  
90 / 1.0  
100% CO2  
75/25 Ar/CO2  
Tri-mix  
Tri-mix  
22 ga.  
Not Recommended  
120 / 1.0  
140 / 1.7  
190 / 2.0  
260 / 3.0  
330 / 5.0  
Not Recommended  
100 / 0.7  
110 / 1.5  
125 / 2.0  
160 / 2.3  
230 / 3.5  
300 / 6.0  
400 / 7.5  
20 ga.  
18 ga.  
16 ga.  
14 ga.  
12 ga.  
10 ga.  
3/16  
100 /1.0  
110 / 1.5  
125 / 2.0  
160 / 2.3  
230 / 3.5  
300 / 6.0  
400 / 7.0  
80 / 1.5  
110 / 2.0  
140 / 2.5  
210 / 3.0  
270 / 5.0  
325 / 6.5  
50 / 0.5  
110 / 2.0  
130 / 2.7  
190 / 3.5  
230 / 6.0  
300 / 7.0  
100 / 2.5  
125 / 3.0  
160 / 3.8  
200 / 5.0  
240 / 6.5  
100 / 2.5  
125 / 3.0  
160 / 3.5  
200 / 4.5  
240 / 7.0  
400 / 2.0  
400 / 2.5  
500 / 7.0  
570 / 9.0  
500 / 7.0  
600 / 7.8  
1/4  
700 / 9.1  
Not  
700 / 8.5  
Not  
Recommended Recommended  
COMMENTS  
below 400  
WFS  
below 400  
WFS  
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B-14  
B-14  
NOTES  
POWER MIG 300  
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C-1  
C-1  
TABLE OF CONTENTS  
- ACCESSORIES -  
Accessories...........................................................................................................................Section C  
Drive Roll Kits .............................................................................................................................C-2  
Push-Pull Feeding Connection Adapter Kit................................................................................C-3  
POWER MIG 300  
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C-2  
C-2  
ACCESSORIES  
English Wire  
Size  
Metric Wire  
DRIVE ROLL KITS  
Length  
Part No.  
Size  
10' (3.0 m)  
12' (3.6 m)  
15' (4.5 m)  
K470-1  
K470-7  
K470-3  
Refer to Table C.1 for various drive roll kits that are  
available for the POWER MIG. All items in Bold are  
supplied standard with the POWER MIG.  
TABLE C.1  
.035 – .045"  
0.9 – 1.2 mm  
Wire  
Size  
Drive Roll Kit  
MAGNUM GUN CONNECTION KIT  
(Optional K466-6)  
.023”-.030” (0.6-0.8 mm)  
.035” (0.9 mm)  
.045” (1.2 mm)  
.040” (1.0mm)  
KP1696-030S  
KP1696-035S  
KP1696-045S  
KP-1696-2  
Solid  
Steel  
Using the optional K466-6 Magnum Connection kit for  
the POWER MIG permits use of standard Magnum  
200, 300 or 400 gun and cable assemblies.  
.035-.045” (0.9-0.2mm)  
.035” (0.9 mm)  
KP-1696-1  
K1692-2 SPOOL GUN (PRINCETM XL)  
When the POWER MIG Gun Selector Switch is in the  
“Standard / Spool Gun” position, the POWER MIG pro-  
vides gun trigger switch transfer between the Magnum  
gun or the spool gun for the same polarity welding with  
different wire and gas processes.  
KP1697-035C  
KP1697-045C  
KP1695-3/64A  
Cored  
.045” (1.2 mm)  
3/64” (1.2 mm)  
Aluminum  
*.035 Aluminum recommended for Push-Pull systems only.  
3/64" (1.2 mm) ALUMINUM  
FEEDING KIT (K2153-1)  
CAUTION  
This kit helps push feeding aluminum through stan-  
dard machine feeder and gun. It provides gun and  
wire drive conversion parts to weld with 3/64" (1.2  
mm) aluminum wire. 5356 alloy aluminum wire is rec-  
ommended for best push feeding performance.  
Closing either gun trigger will cause the electrode of  
both guns to be electrically “HOT”. Be sure unused  
gun is positioned so electrode or tip will not contact  
metal case or other metal common to work.  
-----------------------------------------------------------------------  
Because the control circuitry senses each gun through  
its trigger leads, weld parameters are displayed and  
adjustable for the last gun that was triggered.  
Kit includes drive rolls and wire guide plate for the  
wire drive, liner and two contact tips for the gun, along  
with installation instructions.  
1. Pulling the trigger for the built-in feeder gun  
(Magnum 300):  
K363P READI-REEL ADAPTER  
The K363P Readi-Reel Adapter mounts to the 2"  
spindle. It is needed to mount the 22-30 lb. Readi-  
Reels.  
Disables spool gun operation.  
Changes the displays of the POWER MIG 300 to  
correspond to feeder gun operation.  
Closing feeder gun trigger starts feeder gun weld-  
ing and makes both electrodes electrically “HOT”.  
DUAL CYLINDER MOUNTING KIT  
(K1702-1)  
Permits stable side-by-side mounting of two full size  
(9" dia. x 5' high) gas cylinders with “no lift” loading.  
Simple installation and easy instructions provided.  
Includes upper and lower cylinder supports, wheel  
axles and mounting hardware.  
2. Pulling SPOOL GUN Trigger:  
Disables built-in feeder gun operation.  
Changes the displays of the POWER MIG 300 to  
correspond to Spool Gun operation.  
Closing spool gun trigger starts spool gun welding  
and makes both electrodes electrically “HOT”.  
3. Operation with POWER MIG 300:  
ALTERNATIVE MAGNUM GMAW  
GUN AND CABLE ASSEMBLIES  
Install the spool gun per the installation instructions  
Turn the POWER MIG 300 input power ON.  
Make sure that the Gun Selector Switch is in the  
“Standard / Spool Gun” position.  
The following Magnum 300 gun and cable assemblies  
are separately available for use with the POWER MIG  
300. Each is rated 300 amps 60% duty cycle (or 300  
amps 40% duty) and is equipped with the integrated  
connector, twist-lock trigger connector, fixed nozzle  
and insulator, and includes a liner, diffuser, and con-  
tact tips for the wire sizes specified:  
Pull and release the trigger of the Spool Gun. The  
Power Mig recognizes the spool gun as active and weld  
parameters are adjustable for welding with the Spool  
Gun  
POWER MIG 300  
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C-3  
C-3  
ACCESSORIES  
Non-Synergic Weld Modes (Mode 5)  
Remember: The dialed in SPD value at the POWER  
MIG 300 does not control the WFS at the spool gun.  
Rather, it is adjusting the POWER MIG 300 synergic  
work point. Therefore, adjusting the SPD value will  
not change your actual WFS at the spool gun.  
WFS can only be changed at the spool gun.  
Voltage is adjustable at the power source. The  
right control knob on the power source will  
adjust the voltage that is displayed in the meter  
directly above it.  
The left Display (WFS / AMPS) on the POWER  
MIG 300 will have 4 dashes (----) to indicate  
that the left control knob on the power source is  
inactive. Wire Feed Speed is set at the Spool  
Gun.  
PUSH-PULL FEEDING CONNECTION  
ADAPTER KIT (K2154-1)  
The push-pull adapter kit provides direct connection of  
a Cobra Gold or Prince XL torch to the POWER MIG 300  
wire feeder welder.  
The following procedure settings for Aluminum  
4043 can be used as initial settings for making  
test welds to determine final settings:  
The kit is intended for use with the following Cobra  
Gold or Prince XL torches:  
Wire Dia.  
In. (mm)  
WFS Setting  
Spool Gun  
Arc Voltage  
Setting  
Cobra Gold  
.030" (.8 mm)  
.035" (.9 mm)  
3/64" (1.2 mm)  
270  
250  
240  
15V  
16V  
20V  
Air Cooled 15’(5m) K1589-1 Water-Cooled 15’(5m) K1590-1  
Air Cooled 25’(8m) K1589-2 Water-Cooled 25’(8m) K1590-2  
Air Cooled 50’(15m) K1589-3 Water-Cooled 50’(15m) K1590-3  
4. Synergic Weld Modes  
Prince XL  
Air Cooled 15’(5m) K1591-1 Water-Cooled 15’(5m) K1592-1  
Air Cooled 25’(8m) K1591-2 Water-Cooled 25’(8m) K1592-2  
Air Cooled 50’(15m) K1591-3 Water-Cooled 50’(15m) K1592-3  
The POWER MIG 300 is designed to enable synergic  
weld modes and synergic pulse processes with the  
spool gun. The actual wire feed speed (WFS) of the  
spool gun must be measured and manually set on the  
POWER MIG 300 as a work point for the POWER  
MIG 300 (SPD).  
CAUTION  
Remove all input power to the POWER MIG 300  
before installing the Connection Adapter Kit.  
------------------------------------------------------------------------  
In synergic modes when the spool gun trigger is  
pulled, an adjustable value for the SPD work  
point is displayed in the left meter. The letters  
SPD are displayed in the right meter.  
WARNING  
Refer to the Owner’s Manual of the Torch for  
Amperage and Duty Cycle rating information. The  
torch rating may not match the rating of the power  
source.  
------------------------------------------------------------------------  
MAKING A WELD WITH THE PRINCE XL  
OR COBRA GOLD TORCH INSTALLED  
The left control knob adjusts the SPD value.  
The right control knob is inactive.  
Measure the actual WFS, in inches per minute,  
at the spool gun and set the SPD at the  
POWER MIG 300 to match this value. WFS can  
be measured by pulling the trigger of the spool  
gun and feeding wire for 6 seconds. Measure  
the length of wire (in inches) that was fed and  
multiply by 10.  
• Set the idle roll pressure on the wire drive between  
an indicator reading of 0-2. A recommended start  
point is 1.5.  
• Set the Gun Selection toggle switch located inside  
the wire drive compartment directly above the push-  
pull control cable connector to "PUSH-PULL GUN."  
• Depending on the weld mode, set the Voltage or  
Trim at the POWER MIG 300 using the right control  
knob located on the upper case front panel.  
The POWER MIG 300 is now configured and  
ready to weld in the synergic mode.  
Adjustment of the SPD value from the set value  
has the affect of adjusting trim or arc length.  
To increase the arc length; increase the SPD  
value at the POWER MIG 300 to a value higher  
than the actual WFS.  
• The Wire Feed Speed (WFS) is set using the control  
knob on the Torch. The left control knob on the  
POWER MIG 300 is inactive. The actual WFS being set  
Remember; do not change the WFS at the spool  
gun.  
• To decrease the arc length; decrease the SPD  
value at the POWER MIG 300 to a value lower  
than the actual WFS.  
at the torch is displayed on the POWER MIG 300  
.
• All weld parameters normally available for the active  
weld mode are available during push-pull operation.  
Refer to the Operation Section of this manual.  
POWER MIG 300  
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C-4  
C-4  
NOTES  
POWER MIG 300  
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D-1  
D-1  
TABLE OF CONTENTS  
-MAINTENANCE-  
Maintenance..........................................................................................................................Section D  
Safety Precautions & General Maintenance ...............................................................................D-2  
Liner Removal and Replacement................................................................................................D-3  
POWER MIG 300  
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D-2  
D-2  
MAINTENANCE  
SAFETY PRECAUTIONS  
WARNING  
CONTACT TIP AND GAS NOZZLE  
INSTALLATION  
a. Choose the correct size contact tip for the elec-  
trode being used (wire size is stenciled on the side  
of the contact tip) and screw it snugly into the gas  
diffuser.  
ELECTRIC SHOCK can kill.  
• Have an electrician install and  
service this equipment.  
• Turn the input power off at the  
fuse box before working on  
equipment  
b. Be sure the nozzle insulator is fully screwed onto  
the gun tube and does not block the gas holes in  
the diffuser. (NOTE: Insulator is not required when  
using the optional fixed gas nozzles.)  
• Do not touch electrically hot  
parts.  
c. Slip the appropriate gas nozzle onto the nozzle  
insulator. Adjustable gas nozzles are available with  
a .62” (15.9 mm) or .50” (12.7 mm) I.D., and in both  
standard (flush) and recessed design. The proper  
nozzle should be selected based on the welding  
application. Different length fixed nozzles are also  
available to fit 300 and 400 amp gun tubes to allow  
either spray or short-circuiting transfer welding.  
GENERAL MAINTENANCE  
In extremely dusty locations, dirt may clog the air pas-  
sages causing the welder to run hot. Blow dirt out of  
the welder with low-pressure air at regular intervals to  
eliminate excessive dirt and dust build-up on internal  
parts.  
Choose the gas nozzle as appropriate for the  
GMAW process to be used. Typically, the contact  
tip end should be flush to .12” (3.1 mm) extended  
for the short-circuiting transfer process and .12”  
(3.1 mm) recessed for spray transfer. For the  
Outershield (FCAW) process, 1/8” (3 mm) recess is  
recommended.  
The fan motors have sealed ball bearings which  
require no service.  
DRIVE ROLLS AND GUIDE PLATES  
After every coil of wire, inspect the wire drive mecha-  
nism. Clean it as necessary by blowing with low pres-  
sure compressed air. Do not use solvents for cleaning  
the idle roll because it may wash the lubricant out of  
the bearing. All drive rolls are stamped with the wire  
sizes they will feed. If a wire size other than that  
stamped on the roll is used, the drive roll must be  
changed.  
GUN TUBES AND NOZZLES  
a. Replace worn contact tips as required.  
b. Remove spatter from inside of gas nozzle and from  
tip after each 10 minutes of arc time or as required.  
GUN CABLE CLEANING  
For instructions on replacing or changing drive roll,  
see “Wire Drive Rolls” in Operation section.  
To help prevent feeding problems, clean cable liner  
after using approximately 300 pounds (136 kg) of  
electrode. Remove the cable from the wire feeder and  
lay it out straight on the floor. Remove the contact tip  
from the gun. Using an air hose and only partial pres-  
sure, gently blow out the cable liner from the gas dif-  
fuser end.  
POWER MIG 300  
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D-3  
D-3  
MAINTENANCE  
5. Seat Liner bushing into back of gun. Secure Liner  
by tightening set screw. Do not install the gas dif-  
fuser at this time.  
CAUTION  
Excessive pressure at the start may cause the dirt  
to form a plug.  
6. Lay the cable straight and trim Liner to 9/16”.  
Remove burrs.  
Flex the cable over its entire length and again blow  
out the cable. Repeat this procedure until no further  
dirt comes out. If this has been done and feed prob-  
lems are experienced, try liner replacement, and refer  
to trouble shooting section on rough wire feeding.  
7. Secure the gas diffuser into the tube.  
8. Tighten the set screw against the Liner.  
CAUTION  
LINER REMOVAL AND REPLACEMENT  
(SEE FIGURE D.1)  
This screw should only be gently tightened. Over  
tightening will split or collapse the liner and cause  
poor wire feeding.  
LINER REMOVAL, INSTALLATION AND TRIMMING  
INSTRUCTIONS FOR MAGNUM 300  
------------------------------------------------------------------------  
NOTE: The variation in cable lengths prevents the  
interchangeability of liners between guns. Once a liner  
has been cut for a particular gun, it should not be  
installed in another gun unless it can meet the liner  
cutoff length requirement. Liners are shipped with the  
jacket of the liner extended the proper amount.  
1. Remove the gas nozzle.  
2. Remove the gas diffuser from the gun tube. If gas  
diffuser contains a small set screw, loosen the set  
screw.  
3. Lay gun and cable out straight on a flat surface.  
Loosen set screw of the connector on the back end  
of the gun.  
4. Insert the untrimmed Liner into the back end of the  
gun.  
FIGURE D.1  
FEEDR END  
CABLE HANDLE  
GUN HANDLE  
GUN TUBE  
INSULATION TUBE  
BRASS CABLE  
CONNECTOR  
9/16 (14.3mm)  
LINER TRIM  
LENGTH  
MOLDED GAS PLUG  
SET SCREW  
CLAMPING SCREW  
SET SCREW  
GAS DIFFUSER  
LINER ASSEMBLY (LINER BUSHING TO BE SEATED  
TIGHT AGIANST BRASS CABLE CONNECTOR)  
NOZZLE INSULATION  
GAS NOZZLE  
POWER MIG 300  
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Section E-1  
Section E-1  
TABLE OF CONTENTS  
-THEORY OF OPERATION SECTION-  
Theory of Operation .............................................................................................................Section E  
General Description .......................................................................................................E-2  
Input Voltage and Main Transformer ..............................................................................E-3  
Input Rectifier, Chopper Assembly And Feedback .........................................................E-4  
Diode Control Rectifier and Power Board ......................................................................E-5  
Weld Control Board ........................................................................................................E-6  
Wire Drive Motor and Feedback .....................................................................................E-7  
Thermal Protection, Over Current Protection, and Wire Feeder  
Overload Protection .................................................................................................E-8  
Insulated Gate Bipolar Transistor (IGBT) Operation.......................................................E-9  
Pulse Width Modulation ..........................................................................................E-10  
Chopper Technology Fundamentals........................................................................E-11  
FIGURE E.1 – POWER MIG 300 BLOCK LOGIC DIAGRAM  
MAIN  
TRANSFORMER  
OUTPUT  
RECTIFIER  
CHOPPER  
ASSEMBLY  
POS  
OUTPUT  
TERMINAL  
OUTPUT  
CHOKE  
GUN  
+
IGBT  
+
CURRENT  
TRANSDUCER  
80  
VAC  
60  
VAC  
_
RECONNECT  
PANEL  
NEG  
OUTPUT  
TERMINAL  
CURRENT  
FEEDBACK  
30  
VAC  
POWER  
BOARD  
40 VDC  
20 VDC  
PWM  
115  
VAC  
LINE  
VOLTAGE  
FEEDBACK  
SWITCH  
DIODE CONTROL  
RECTIFIER  
SIGNALS  
+15/-15/+5 VDC  
IGBT  
DRIVE  
RELAY  
CHOPPER  
RS232  
CONNECTOR  
FAN  
WELD CONTROL BOARD  
MOTOR  
40  
VDC  
SEC  
TO FAN RELAY  
FROM WELD  
CONTROL BOARD  
THERMOSTATS  
ARCLINK  
+5 VDC  
SHIELDED CABLE AND SPI COMMUNICATIONS  
FOOT AMPTROL OR REMOTE (6-PIN AMPHENOL)  
SPOOL  
40 VDC  
DISPLAY  
BOARD  
ENCODER  
BOARD  
(Below code 10900)  
SHIELDED  
CABLE  
MSP  
BOARD  
FEEDER  
BOARD  
24 VDC  
GUN  
BOARD  
GUN TRIGGER AND THUMB SWITCH  
SPOOL GUN OR PUSH-PULL GUN (7-PIN AMPHENOL)  
SPOOL GUN  
PUSH-PULL  
SWITCH  
T
GAS  
SOLENOID  
A
C
H
Mechanical Encoders  
(Above code 10900)  
WIRE DRIVE  
MOTOR  
POWER MIG 300  
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E-2  
E-2  
THEORY OF OPERATION  
FIGURE E.2 – INPUT VOLTAGE AND MAIN TRANSFORMER  
MAIN  
TRANSFORMER  
OUTPUT  
RECTIFIER  
CHOPPER  
ASSEMBLY  
POS  
OUTPUT  
TERMINAL  
OUTPUT  
CHOKE  
GUN  
+
IGBT  
+
CURRENT  
TRANSDUCER  
80  
VAC  
60  
VAC  
_
RECONNECT  
PANEL  
NEG  
OUTPUT  
TERMINAL  
CURRENT  
FEEDBACK  
30  
VAC  
POWER  
BOARD  
40 VDC  
20 VDC  
PWM  
115  
VAC  
LINE  
VOLTAGE  
FEEDBACK  
SWITCH  
DIODE CONTROL  
RECTIFIER  
SIGNALS  
+15/-15/+5 VDC  
IGBT  
DRIVE  
RELAY  
CHOPPER  
RS232  
CONNECTOR  
FAN  
WELD CONTROL BOARD  
MOTOR  
40  
VDC  
SEC  
TO FAN RELAY  
FROM WELD  
CONTROL BOARD  
THERMOSTATS  
ARCLINK  
+5 VDC  
SHIELDED CABLE AND SPI COMMUNICATIONS  
FOOT AMPTROL OR REMOTE (6-PIN AMPHENOL)  
SPOOL  
40 VDC  
DISPLAY  
BOARD  
ENCODER  
BOARD  
(Below code 10900)  
SHIELDED  
CABLE  
MSP  
BOARD  
FEEDER  
BOARD  
24 VDC  
GUN  
BOARD  
GUN TRIGGER AND THUMB SWITCH  
SPOOL GUN OR PUSH-PULL GUN (7-PIN AMPHENOL)  
SPOOL GUN  
PUSH-PULL  
SWITCH  
T
GAS  
SOLENOID  
A
C
H
Mechanical Encoders  
(Above code 10900)  
WIRE DRIVE  
MOTOR  
GENERAL DESCRIPTION  
The Power MIG 300 is a complete semiautomatic,  
multi-process DC arc welding machine offering CV and  
CC DC welding. It is rated for 300 amps, 32 volts, at  
60% duty cycle. The standard machine is equipped to  
weld CC Stick, CC-GTAW, CV-FCAW, and synergic  
and non-synergic CV GMAW/GMAW-P, Pulse-on-  
Pulse, and Power Mode welding processes.  
The digital microcomputer based control system allows  
easy and accurate adjustment of weld parameters  
through the multi-process panel located on the front of  
the machine. The Power MIG 300 is equipped with a  
6-pin connector for a foot amptrol or remotes and a 7-  
pin connector to allow operation of a spool gun or a  
push-pull gun for feeding aluminum wires.  
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.  
POWER MIG 300  
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E-3  
E-3  
THEORY OF OPERATION  
FIGURE E.3 – INPUT RECTIFIER, CHOPPER ASSEMBLY AND FEEDBACK  
MAIN  
TRANSFORMER  
OUTPUT  
RECTIFIER  
CHOPPER  
ASSEMBLY  
POS  
OUTPUT  
TERMINAL  
OUTPUT  
CHOKE  
GUN  
+
IGBT  
+
CURRENT  
TRANSDUCER  
80  
VAC  
60  
VAC  
_
RECONNECT  
PANEL  
NEG  
OUTPUT  
TERMINAL  
CURRENT  
FEEDBACK  
30  
VAC  
POWER  
BOARD  
40 VDC  
20 VDC  
PWM  
115  
VAC  
LINE  
SWITCH  
VOLTAGE  
FEEDBACK  
DIODE CONTROL  
RECTIFIER  
SIGNALS  
+15/-15/+5 VDC  
IGBT  
DRIVE  
RELAY  
CHOPPER  
RS232  
CONNECTOR  
FAN  
WELD CONTROL BOARD  
MOTOR  
40  
VDC  
SEC  
TO FAN RELAY  
FROM WELD  
CONTROL BOARD  
THERMOSTATS  
ARCLINK  
+5 VDC  
SHIELDED CABLE AND SPI COMMUNICATIONS  
FOOT AMPTROL OR REMOTE (6-PIN AMPHENOL)  
40 VDC  
SPOOL  
GUN  
BOARD  
DISPLAY  
BOARD  
ENCODER  
BOARD  
(Below code 10900)  
SHIELDED  
CABLE  
MSP  
BOARD  
FEEDER  
BOARD  
24 VDC  
GUN TRIGGER AND THUMB SWITCH  
SPOOL GUN OR PUSH-PULL GUN (7-PIN AMPHENOL)  
SPOOL GUN  
PUSH-PULL  
SWITCH  
T
GAS  
SOLENOID  
A
C
H
Mechanical Encoders  
(Above code 10900)  
WIRE DRIVE  
MOTOR  
INPUT VOLTAGE AND MAIN TRANS-  
FORMER  
Single-phase input power is brought into the rear of the  
Power MIG 300 through a three-prong plug and input  
cable. A reconnect panel, also located on the rear of  
the machine, allows the user to configure the Power  
MIG 300 for either 230V, 460V, or 575V input supply  
power. An ON/OFF line switch is located on the front  
panel. When the line switch is ON, AC input voltage is  
applied to the primary winding of the main transformer.  
The main transformer converts the high voltage, low  
current input power to a low voltage, high current out-  
put. The main transformer also has two isolated auxil-  
iary windings. One supplies 30 VAC to a Diode Control  
Rectifier, which converts the 30 VAC to 40 VDC to sup-  
ply the Power Board and the Spool Gun Board. The  
Power Board in turn supplies 20  
VDC to the Chopper Board and +15 VDC, -15 VDC and  
+5 VDC to the Weld Control Board circuitry. The other  
auxiliary winding provides 115 VAC to operate a ther-  
mostatically controlled fan motor through a relay, which  
also receives signals from the Weld Control Board.  
The fan is designed to come on automatically when the  
trigger is pulled. The fan will stay on as needed for a  
minimum of six minutes after the weld arc is terminat-  
ed. The fan will also stay on when the machine's weld-  
ing and feeding are disabled during thermostatic over-  
temperature protection. (See Thermal and Overload  
Protection.)  
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.  
POWER MIG 300  
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E-4  
E-4  
THEORY OF OPERATION  
FIGURE E.4 – DIODE CONTROL RECTIFIER AND POWER BOARD  
MAIN  
TRANSFORMER  
OUTPUT  
RECTIFIER  
CHOPPER  
ASSEMBLY  
POS  
OUTPUT  
TERMINAL  
OUTPUT  
CHOKE  
GUN  
+
IGBT  
+
CURRENT  
TRANSDUCER  
80  
VAC  
60  
VAC  
_
RECONNECT  
PANEL  
NEG  
OUTPUT  
TERMINAL  
CURRENT  
FEEDBACK  
30  
VAC  
POWER  
BOARD  
40 VDC  
20 VDC  
PWM  
115  
VAC  
LINE  
VOLTAGE  
FEEDBACK  
SWITCH  
DIODE CONTROL  
RECTIFIER  
SIGNALS  
+15/-15/+5 VDC  
IGBT  
DRIVE  
RELAY  
CHOPPER  
RS232  
CONNECTOR  
FAN  
MOTOR  
WELD CONTROL BOARD  
40  
VDC  
SEC  
TO FAN RELAY  
FROM WELD  
CONTROL BOARD  
THERMOSTATS  
ARCLINK  
+5 VDC  
SHIELDED CABLE AND SPI COMMUNICATIONS  
FOOT AMPTROL OR REMOTE (6-PIN AMPHENOL)  
SPOOL  
40 VDC  
DISPLAY  
BOARD  
ENCODER  
BOARD  
(Below code 10900)  
SHIELDED  
CABLE  
MSP  
BOARD  
FEEDER  
BOARD  
24 VDC  
GUN  
BOARD  
GUN TRIGGER AND THUMB SWITCH  
SPOOL GUN OR PUSH-PULL GUN (7-PIN AMPHENOL)  
SPOOL GUN  
PUSH-PULL  
SWITCH  
T
GAS  
SOLENOID  
A
C
H
Mechanical Encoders  
(Above code 10900)  
WIRE DRIVE  
MOTOR  
INPUT  
RECTIFIER,  
CHOPPER  
ASSEMBLY AND FEEDBACK  
The 60 VAC output from the main transformer sec-  
ondary is connected to an input rectifier. The resultant  
80 VDC is applied to four parallel capacitors incorpo-  
rated within the Chopper Assembly. These capacitors  
function as filters and also as power supplies for the  
insulated gate bipolar transistors or IGBT. See IGBT  
Operation in this section. The IGBT acts as a high-  
speed switch operating at 20KHZ. This device is  
switched on and off by the Weld Control Board through  
pulse width modulation circuitry. See Pulse Width  
Modulation in this section. This "chopped" DC output  
is applied through an output choke coil to the positive  
output terminal and through a current transducer to the  
negative output terminal. The choke functions as a  
current filter. A free-wheeling diode is incorporated in  
the Chopper Assembly to provide a current path for the  
stored energy in the choke when the IGBT is turned off.  
See Chopper Technology Fundamentals in this sec-  
tion.  
Output voltage and current feedback information is fed  
to the Weld Control Board. This information is sensed  
from the current transducer and voltage sense circuitry  
on the output terminal circuits. If current or voltage  
become abnormally high, the Weld Control Board will  
shut off the IGBTs, thus disabling the machine's output.  
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.  
POWER MIG 300  
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E-5  
E-5  
THEORY OF OPERATION  
FIGURE E.5 – WELD CONTROL BOARD  
MAIN  
TRANSFORMER  
OUTPUT  
RECTIFIER  
CHOPPER  
ASSEMBLY  
POS  
OUTPUT  
TERMINAL  
OUTPUT  
CHOKE  
GUN  
+
IGBT  
+
CURRENT  
TRANSDUCER  
80  
VAC  
60  
VAC  
_
RECONNECT  
PANEL  
NEG  
OUTPUT  
TERMINAL  
CURRENT  
FEEDBACK  
30  
VAC  
POWER  
BOARD  
40 VDC  
20 VDC  
PWM  
115  
VAC  
LINE  
VOLTAGE  
FEEDBACK  
SWITCH  
DIODE CONTROL  
RECTIFIER  
SIGNALS  
+15/-15/+5 VDC  
IGBT  
DRIVE  
RELAY  
CHOPPER  
RS232  
CONNECTOR  
FAN  
WELD CONTROL BOARD  
MOTOR  
40  
VDC  
SEC  
TO FAN RELAY  
FROM WELD  
CONTROL BOARD  
THERMOSTATS  
ARCLINK  
+5 VDC  
SHIELDED CABLE AND SPI COMMUNICATIONS  
FOOT AMPTROL OR REMOTE (6-PIN AMPHENOL)  
SPOOL  
40 VDC  
DISPLAY  
BOARD  
ENCODER  
BOARD  
(Below code 10900)  
SHIELDED  
CABLE  
MSP  
BOARD  
FEEDER  
BOARD  
24 VDC  
GUN  
BOARD  
GUN TRIGGER AND THUMB SWITCH  
SPOOL GUN OR PUSH-PULL GUN (7-PIN AMPHENOL)  
SPOOL GUN  
PUSH-PULL  
SWITCH  
T
GAS  
SOLENOID  
A
C
H
Mechanical Encoders  
(Above code 10900)  
WIRE DRIVE  
MOTOR  
DIODE CONTROL RECTIFIER AND  
POWER BOARD  
The Power Board receives approximately 40 VDC from  
the Diode Control Rectifier. In turn, the Power Board  
supplies a variety of regulated DC voltages to the Weld  
Control Board, which it uses to power its many circuits  
and communication functions. The Power Board also  
supplies +20 VDC to the Chopper Assembly.  
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.  
POWER MIG 300  
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E-6  
E-6  
THEORY OF OPERATION  
FIGURE E.6 – WIRE DRIVE MOTOR AND FEEDBACK  
MAIN  
TRANSFORMER  
OUTPUT  
RECTIFIER  
CHOPPER  
ASSEMBLY  
POS  
OUTPUT  
TERMINAL  
OUTPUT  
CHOKE  
GUN  
+
IGBT  
+
CURRENT  
TRANSDUCER  
80  
VAC  
60  
VAC  
_
RECONNECT  
PANEL  
NEG  
OUTPUT  
TERMINAL  
CURRENT  
FEEDBACK  
30  
VAC  
POWER  
BOARD  
40 VDC  
20 VDC  
PWM  
115  
VAC  
LINE  
VOLTAGE  
FEEDBACK  
SWITCH  
DIODE CONTROL  
RECTIFIER  
SIGNALS  
+15/-15/+5 VDC  
IGBT  
DRIVE  
RELAY  
CHOPPER  
RS232  
CONNECTOR  
FAN  
MOTOR  
WELD CONTROL BOARD  
40  
VDC  
SEC  
TO FAN RELAY  
FROM WELD  
CONTROL BOARD  
THERMOSTATS  
ARCLINK  
+5 VDC  
SHIELDED CABLE AND SPI COMMUNICATIONS  
FOOT AMPTROL OR REMOTE (6-PIN AMPHENOL)  
SPOOL  
40 VDC  
DISPLAY  
BOARD  
ENCODER  
BOARD  
(Below code 10900)  
SHIELDED  
CABLE  
MSP  
BOARD  
FEEDER  
BOARD  
24 VDC  
GUN  
BOARD  
GUN TRIGGER AND THUMB SWITCH  
SPOOL GUN OR PUSH-PULL GUN (7-PIN AMPHENOL)  
SPOOL GUN  
PUSH-PULL  
SWITCH  
T
GAS  
SOLENOID  
A
C
H
Mechanical Encoders  
(Above code 10900)  
WIRE DRIVE  
MOTOR  
WELD CONTROL BOARD  
In addition, the Weld Control Board monitors the  
Chopper thermostat and the Main Transformer sec-  
ondary winding thermostat. In the event of a fault con-  
dition, the Weld Control Board will activate the thermal  
light and will disable or reduce the machine output.  
The Weld Control Board performs the primary interfac-  
ing functions to establish and maintain output control of  
the Power MIG 300 machine. The function generator  
and weld files reside within the Weld Control Board  
hardware and software. Digital command signals and  
feedback information from other machine components  
are received and processed at the Weld Control Board.  
Software within the Weld Control Board processes the  
command and feedback information and sends the  
appropriate pulse width modulation (PWM) signals to  
the Chopper Assembly IGBT. (See Pulse Width  
Modulation in this section.) In this manner, a digitally  
controlled high-speed welding waveform is created.  
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.  
POWER MIG 300  
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E-7  
E-7  
THEORY OF OPERATION  
FIGURE E.7 – WIRE DRIVE MOTOR AND FEEDBACK  
MAIN  
TRANSFORMER  
OUTPUT  
RECTIFIER  
CHOPPER  
ASSEMBLY  
POS  
OUTPUT  
TERMINAL  
OUTPUT  
CHOKE  
GUN  
+
IGBT  
+
CURRENT  
TRANSDUCER  
80  
VAC  
60  
VAC  
_
RECONNECT  
PANEL  
NEG  
OUTPUT  
TERMINAL  
CURRENT  
FEEDBACK  
30  
VAC  
POWER  
BOARD  
40 VDC  
20 VDC  
115  
VAC  
LINE  
VOLTAGE  
FEEDBACK  
SWITCH  
PWM  
DIODE CONTROL  
RECTIFIER  
SIGNALS  
+15/-15/+5 VDC  
IGBT  
DRIVE  
RELAY  
CHOPPER  
RS232  
CONNECTOR  
FAN  
MOTOR  
WELD CONTROL BOARD  
40  
VDC  
SEC  
TO FAN RELAY  
FROM WELD  
CONTROL BOARD  
THERMOSTATS  
ARCLINK  
+5 VDC  
SHIELDED CABLE AND SPI COMMUNICATIONS  
FOOT AMPTROL OR REMOTE (6-PIN AMPHENOL)  
SPOOL  
40 VDC  
DISPLAY  
BOARD  
ENCODER  
BOARD  
(Below code 10900)  
SHIELDED  
CABLE  
MSP  
BOARD  
FEEDER  
BOARD  
24 VDC  
GUN  
BOARD  
GUN TRIGGER AND THUMB SWITCH  
SPOOL GUN OR PUSH-PULL GUN (7-PIN AMPHENOL)  
SPOOL GUN  
PUSH-PULL  
SWITCH  
T
GAS  
SOLENOID  
A
C
H
Mechanical Encoders  
(Above code 10900)  
WIRE DRIVE  
MOTOR  
WIRE DRIVE MOTOR AND FEED-  
BACK  
The Wire Drive Motor is controlled by the Feeder Board  
and the Weld Control Board. A motor speed feedback  
signal is generated at the motor Tach and sent to the  
Feeder Board, which compares this feedback signal to  
the commands from the Encoder. It then sends the  
appropriate armature voltage to the Wire Drive Motor.  
This controlled wire drive speed in turn regulates the  
electrode wire feed speed through the gun.  
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.  
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E-8  
E-8  
THEORY OF OPERATION  
THERMAL PROTECTION  
OVER CURRENT PROTECTION  
Two normally closed (NC) thermostats protect the  
machine from excessive operating temperatures.  
These thermostats are wired in series and are con-  
nected to the Weld Control board. One of the ther-  
mostats is located on the Chopper Assembly board,  
and one is on the secondary of the Main Transformer.  
Excessive temperatures may be caused by a lack of  
cooling air or by operating the machine beyond its duty  
cycle or output rating. If excessive operating tempera-  
tures should occur, the thermostats will prevent output  
from the machine. The yellow thermal light, located on  
the front of the machine, will be illuminated. The ther-  
mostats are self resetting once the machine cools suf-  
ficiently. If the thermostat shutdown was caused by  
excessive output or duty cycle and the fan is operating  
normally, the power switch may be left on and the reset  
should occur within a 15-minute period. If the fan is not  
turning or the intake air louvers are obstructed, the  
power must be removed from the machine and the fan  
condition or air obstruction corrected. The cooling fan  
runs only when necessary. The F.A.N. (fan as needed)  
system is controlled by the Weld Control Board via  
solid state relay.  
If the average current exceeds 300 to 320 amps, the  
peak current will be limited to 100 amps until the sys-  
tem is re-triggered or the average current decreases to  
under 50 amps.  
WIRE FEEDER OVERLOAD PRO-  
TECTION  
The Power MIG 300 wire drive motor has its own solid  
state overload protection. If the motor becomes over-  
loaded, the protection circuitry turns off the wire feed  
and the gas solenoid. Overload may result from  
improperly sized tip liner and drive rolls, obstructions or  
bends in the gun cable, and any other factors that  
would impede the wire feeding. To resume welding,  
simply pull the gun trigger. There is no circuit breaker  
to reset, as the protection is provided by reliable solid  
state electronics.  
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E-9  
E-9  
THEORY OF OPERATION  
FIGURE E.8 – IGBT OPERATION  
POSITIVE  
VOLTAGE  
APPLIED  
GATE  
GATE  
SOURCE  
SOURCE  
n +  
n +  
n +  
n +  
p
BODY REGION  
p
BODY REGION  
DRAIN DRIFT REGION  
DRAIN DRIFT REGION  
n -  
n -  
n +  
p +  
BUFFER LAYER  
n +  
p +  
BUFFER LAYER  
INJECTING LAYER  
INJECTING LAYER  
DRAIN  
DRAIN  
B. ACTIVE  
A. PASSIVE  
INSULATED GATE BIPOLAR  
TRANSISTOR (IGBT) OPERATION  
An IGBT is a type of transistor. IGBTs are semiconduc-  
tors well suited for high frequency switching and high  
current applications.  
Drawing B shows the IGBT in an active mode. When  
the gate signal, a positive DC voltage relative to the  
source, is applied to the gate terminal of the IGBT, it is  
capable of conducting current. A voltage supply con-  
nected to the drain terminal will allow the IGBT to con-  
duct and supply current to circuit components coupled  
to the source. Current will flow through the conducting  
IGBT to downstream components as long as the posi-  
tive gate signal is present. This is similar to turning ON  
a light switch.  
Drawing A shows an IGBT in a passive mode. There is  
no gate signal, zero volts relative to the source, and  
therefore, no current flow. The drain terminal of the  
IGBT may be connected to a voltage supply; but since  
there is no conduction the circuit will not supply current  
to components connected to the source. The circuit is  
turned off like a light switch in the OFF position.  
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E-10  
E-10  
THEORY OF OPERATION  
FIGURE E.9 – TYPICAL IGBT OUTPUTS  
sec  
48  
sec  
sec  
sec  
50  
MINIMUM OUTPUT  
sec  
24  
sec  
sec  
24  
2
sec  
50  
MAXIMUM OUTPUT  
PULSE WIDTH MODULATION  
IGBT group conducting for 1 microsecond. The nega-  
tive portion is the other IGBT group. The dwell time  
(off time) is 48 microseconds (both IGBT groups off).  
Since only 2 microseconds of the 50-microsecond time  
period is devoted to conducting, the output power is  
minimized.  
The term PULSE WIDTH MODULATION is used to  
describe how much time is devoted to conduction in  
the positive and negative portions of the cycle.  
Changing the pulse width is known as MODULATION.  
Pulse Width Modulation (PWM) is the varying of the  
pulse width over the allowed range of a cycle to affect  
the output of the machine.  
MAXIMUM OUTPUT  
MINIMUM OUTPUT  
By holding the gate signals on for 48 microseconds  
each and allowing only 2 microseconds of dwell time  
(off time) during the 50-microsecond cycle, the output is  
maximized. The darkened area under the top curve  
can be compared to the area under the bottom curve.  
The more dark area under the curve, the more power is  
present.  
By controlling the duration of the gate signal, the IGBT  
is turned on and off for different durations during a  
cycle. The top drawing below shows the minimum out-  
put signal possible over a 50-microsecond time period.  
The positive portion of the signal represents one  
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E-11  
E-11  
THEORY OF OPERATION  
CHOPPER TECHNOLOGY  
FUNDAMENTALS  
The new era of welding machines such as the Power  
MIG 300 employ a technology whereby a DC source is  
turned on and off (chopped up) at high speed, then  
smoothed through an inductor to control an arc.  
Hence the name “Chopper.” The biggest advantage of  
chopper technology is the high-speed control of the  
arc, similar to the inverter machines. A block diagram  
for this is as follows:  
FIGURE E.10  
SOLID STATE  
SWITCH  
INDUCTOR  
AND DIODE  
DC RECTIFIER  
AND FILTER  
SINGLE-PHASE  
INPUT POWER  
ARC  
ARC  
CONTROL  
+
ARC  
80VDC  
DIODE  
CURRENT WITH SWITCH OPEN  
_
INDUCTOR  
SWITCH  
CURRENT WITH SWITCH CLOSED  
In this system, the engine drives a three-phase alternator, which generates power that is rectified and filtered to  
produce about 80VDC. The current is applied through a solid state switch to an inductor. By turning the switch  
on and off, current in the inductor and the arc can be controlled. The above diagram depicts the current flow in  
the system when the switch is open and closed:  
When the switch is closed, current is applied through the inductor to the arc. When the switch opens, current  
stored in the inductor sustains flow in the arc and through the diode. The repetition rate of switch closure is 20Khz,  
which allows ultra-fast control of the arc. By varying the ratio of on time versus off time of the switch (Duty Cycle),  
the current applied to the arc is controlled. This is the basis for Chopper Technology: Controlling the switch in such  
a way as to produce superior welding.  
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Section F-1  
Section F-1  
TABLE OF CONTENTS  
TROUBLESHOOTING & REPAIR SECTION  
Troubleshooting & Repair Section ................................................................................Section F  
How to Use Troubleshooting Guide.......................................................................................F-2  
PC Board Troubleshooting Procedures .................................................................................F-3  
Troubleshooting Guide ................................................................................................F-4 - F-11  
Chopper Board Capacitor Discharge Procedure ..........................................................F-12  
Main Transformer Test ..................................................................................................F-14  
Chopper Board Test ......................................................................................................F-16  
Control Rectifier Test .....................................................................................................F-19  
Output Rectifier Assembly Test ....................................................................................F-21  
Wire Drive Motor and Tachometer Feedback Test .......................................................F-23  
Encoder PC Board Test (10562 & Above).....................................................................F-26  
Current Transducer Test................................................................................................F-29  
Power Mig Scrolling Dashes Test..................................................................................F-32  
Oscilloscope Waveforms......................................................................................................F-34  
Removal and Replacement Procedures..............................................................................F-36  
Motor & Gear Box Removal and Replacement.............................................................F-36  
Output Rectifier Removal and Replacement.................................................................F-40  
Chopper Board Assembly Removal and Replacement.................................................F-43  
Main Transformer and Output Choke Removal and Replacement ...............................F-46  
Fan Motor Assembly Removal and Replacement.........................................................F-50  
Voltage & Current Calibration Procedure......................................................................F-52  
Retest after Repair...............................................................................................................F-57  
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F-2  
F-2  
TROUBLESHOOTING & REPAIR  
HOW TO USE TROUBLESHOOTING GUIDE  
WARNING  
Service and repair should be performed by only Lincoln Electric Factory Trained Personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician and machine  
operator and will invalidate your factory warranty. For your safety and to avoid Electrical Shock, please  
observe all safety notes and precautions detailed throughout this manual.  
This Troubleshooting Guide is provided to help  
you locate and repair possible machine malfunc-  
tions. Simply follow the three-step procedure list-  
ed below.  
Step 3. PERFORM COMPONENT TESTS. The  
last column, labeled “Recommended Course of  
Action” lists the most likely components that may  
have failed in your machine. It also specifies the  
appropriate test procedure to verify that the sub-  
ject component is either good or bad. If there are  
a number of possible components, check the  
components in the order listed to eliminate one  
possibility at a time until you locate the cause of  
your problem.  
Step 1. LOCATE PROBLEM (SYMPTOM). Look  
under the column labeled “PROBLEM” (SYMP-  
TOMS). This column describes possible symp-  
toms that the machine may exhibit. Find the list-  
ing that best describes the symptom that the  
machine is exhibiting. Symptoms are grouped  
into four main categories: Output Problems,  
Function Problems, Wire Feeding, and Welding  
Problems.  
All of the referenced test procedures referred to in  
the Troubleshooting Guide are described in detail  
at the end of this section.  
Refer to the  
Troubleshooting and Repair Table of Contents  
to locate each specific Test Procedure. All of the  
referred to test points, components, terminal  
strips, etc., can be found on the referenced elec-  
trical wiring diagrams and schematics. Refer to  
the Machine Schematic and Electrical  
Diagrams Section Table of Contents to locate the  
appropriate diagram.  
Step 2. PERFORM EXTERNAL TESTS. The  
second column, labeled “POSSIBLE AREAS OF  
MISADJUSTMENT(S)”, lists the obvious external  
possibilities that may contribute to the machine  
symptom. Perform these tests/checks in the  
order listed. In general, these tests can be con-  
ducted without removing the case cover.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs  
safely, contact the Lincoln Electric Service Department for electrical troubleshooting assistance before  
you proceed. Call 1-800-833-9353.  
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F-3  
F-3  
TROUBLESHOOTING & REPAIR  
PC BOARD TROUBLESHOOTING PROCEDURES  
- Remove the PC board from the static-shielding bag  
and place it directly into the equipment. Don’t set the  
PC board on or near paper, plastic or cloth which  
could have a static charge. If the PC board can’t be  
installed immediately, put it back in the static-shield-  
ing bag.  
WARNING  
ELECTRIC SHOCK  
can kill.  
Have an electrician install and  
service this equipment. Turn the  
input power OFF at the fuse box  
before working on equipment. Do  
not touch electrically hot parts.  
- If the PC board uses protective shorting jumpers,  
don’t remove them until installation is complete.  
- If you return a PC board to The Lincoln Electric  
Company for credit, it must be in the static-shielding  
bag. This will prevent further damage and allow prop-  
er failure analysis.  
CAUTION  
Sometimes machine failures appear to be due to PC  
board failures. These problems can sometimes be  
traced to poor electrical connections. To avoid prob-  
lems when troubleshooting and replacing PC boards,  
please use the following procedure:  
4. Test the machine to determine if the failure  
symptom has been corrected by the  
replacement PC board.  
NOTE: It is desirable to have a spare (known good)  
PC board available for PC board troubleshooting.  
1. Determine to the best of your technical ability  
that the PC board is the most likely component  
causing the failure symptom.  
NOTE: Allow the machine to heat up so that all  
electrical components can reach their operating  
temperature.  
2. Check for loose connections at the PC board to  
assure that the PC board is properly connected.  
5. Remove the replacement PC board and  
substitute it with the original PC board to  
recreate the original problem.  
3. If the problem persists, replace the suspect PC  
board using standard practices to avoid static  
electrical damage and electrical shock. Read  
the warning inside the static resistant bag and  
perform the following procedures:  
a. If the original problem does not reappear by  
substituting the original board, then the PC  
board was not the problem. Continue to look  
for bad connections in the control wiring  
harness, junction blocks, and terminal strips.  
PC board can be damaged by static electricity.  
b. If the original problem is recreated by the  
substitution of the original board, then the PC  
board was the problem. Reinstall the  
replacement PC board and test the machine.  
- Remove your body’s static  
charge before opening the static-  
shielding bag. Wear an anti-static  
wrist strap. For safety, use a 1  
Meg ohm resistive cord connected  
6. Always indicate that this procedure was  
followed when warranty reports are to be  
submitted.  
to  
a
grounded part of the  
equipment frame.  
ATTENTION  
Static-Sensitive  
Devices  
Handle only at  
Static-Safe  
- If you don’t have a wrist strap,  
touch an un-painted, grounded,  
part of the equipment frame. Keep  
touching the frame to prevent  
static build-up. Be sure not to  
touch any electrically live parts at  
the same time.  
NOTE: Following this procedure and writing on the  
warranty report, “INSTALLED AND SWITCHED PC  
BOARDS TO VERIFY PROBLEM,” will help avoid  
denial of legitimate PC board warranty claims.  
Workstations  
- Tools which come in contact with the PC board must  
be either conductive, anti-static or static-dissipative.  
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F-4  
F-4  
TROUBLESHOOTING & REPAIR  
Observe Safety Guidelines  
detailed in the beginning of this manual.  
TROUBLESHOOTING GUIDE  
PROBLEMS  
POSSIBLE AREAS OF  
RECOMMENDED  
(SYMPTOMS)  
MISADJUSTMENT(S)  
COURSE OF ACTION  
OUTPUT PROBLEMS  
Major physical or electrical damage 1. Contact your local Lincoln 1. Contact the Lincoln Electric  
is evident.  
Authorized  
Facility.  
Field  
Service  
Service Department at 1-800-  
833-9353 (WELD).  
Machine is dead - no welding out-  
put and no wire feed when gun  
trigger is pulled.  
1. Make certain that the input power 1. Check for the correct input volt-  
switch is in the "ON" position.  
age at the line switch. (L1-L2)  
See Wiring Diagram.  
2. Check the input voltage at the  
machine. Input voltage must 2. Check for loose or faulty con-  
match the rating plate and the  
reconnect panel.  
nections between the line  
switch and the reconnect panel.  
3. Blown or missing fuses in the 3. Perform the Main Transformer  
input line. Test.  
4. Check for thermal light on case 4. Check the red LED’s (1 & 2) on  
front. Thermostats may be open  
due to machine overheating. If  
machine operates normally after  
a cooling off period then check  
for proper fan operation and ven-  
tilation. Make certain that the  
machine’s duty cycle is not being  
exceeded.  
the digital power supply board.  
They should be lit indicating  
that DC voltage is being applied  
to plugs J42 and J43. See  
Wiring Diagram.  
If LED’s 1 & 2 are not lit check  
for the presence of 42 VDC at  
plug J41 pin 2(+) and pin 1(-). If  
the 42 VDC is present and  
LED’s 1 & 2 are not lit the digital  
power supply board may be  
faulty.  
5. Remove the gun trigger connec-  
tion and jump the two connec-  
tions at the machine. If you  
have a wirefeed gun, it may be  
faulty. Replace.  
If the 42 VDC is not present at  
plug J41 perform the Control  
Rectifier Test.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
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F-5  
F-5  
TROUBLESHOOTING & REPAIR  
TROUBLESHOOTING GUIDE  
Observe Safety Guidelines  
detailed in the beginning of this manual.  
PROBLEMS  
(SYMPTOMS)  
POSSIBLE AREAS OF  
MISADJUSTMENT(S)  
RECOMMENDED  
COURSE OF ACTION  
OUTPUT PROBLEMS  
No welding output but wire feeds 1. Check the input voltage at the 1. Check for loose or broken con-  
normally when gun trigger is pulled.  
machine. Input voltage must  
match the rating plate and the  
reconnect panel.  
nections at the output terminals,  
the choke and all heavy current  
carrying leads. See the Machine  
Schematic.  
2. The gun may be faulty. Check for  
continuity.  
2. Make sure that the transformer  
secondary leads are securely  
connected to the Output Rectifier  
assembly.  
3. Check continuity through the  
work lead.  
3. Check for OCV at output studs  
when trigger is pulled. If OCV is  
present, the gun may be faulty.  
Replace.  
4. Check for 57VAC at the input of  
output rectifier. If reading is not  
correct  
Perform  
Main  
Transformer Tests. If you mea-  
sure approximately 57 VAC,  
check for 80VDC at the output of  
the output rectifier. If reading is  
not correct perform the Output  
Rectifier Assembly Tests. If  
80VDC is there Perform  
Chopper Board Test.  
5. Check for 15VDC input to the  
Control Board at leads 12J4  
(412) to 10J4 (410), -15VDC at  
leads 11J4 (411) to 10J4 (410),  
5VDC at leads 8J4 (408) to 10J4  
(410). If missing a voltage check  
wiring back to Digital Power  
Supply PCB. If voltage is ok, the  
Control Board may be faulty.  
Replace.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
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F-6  
F-6  
TROUBLESHOOTING & REPAIR  
Observe Safety Guidelines  
detailed in the beginning of this manual.  
TROUBLESHOOTING GUIDE  
PROBLEMS  
POSSIBLE AREAS OF  
RECOMMENDED  
(SYMPTOMS)  
MISADJUSTMENT(S)  
COURSE OF ACTION  
OUTPUT PROBLEMS  
Wire feeds but welding output is 1. Make sure that the proper wire 1. Check for loose or faulty con-  
low causing wire to “stub”. Welds  
are “cold”. Machine cannot obtain  
full rated output of 300 amps at 32 2. Check gun and work cable for  
volts. loose or faulty connections.  
and procedures are being used.  
nections of the heavy current  
carrying leads.  
Diagram  
See Wiring  
2. Perform  
the  
Current  
Transducer Test.  
3. Perform Output Waveform  
Test.  
4. Perform the Output Rectifier  
Assembly Tests  
5. The Control Board may be faulty.  
Replace.  
The output voltage and wire feed is 1. Remove the gun. If the problem 1. Find J85 on Feed Head Board  
present continuously or pulsing  
when gun trigger is NOT activated.  
is resolved, the gun trigger cir-  
cuit is faulty. Repair or replace.  
and unplug. If the problem still  
exist Feed Head Board may be  
faulty.  
2. If problem persists when gun  
assembly is removed from  
machine, then the problem is  
within the POWER MIG 300.  
The output voltage is present con-  
tinuously when gun trigger is NOT  
activated. The wire is not feeding.  
1. Find J6 on Control PCB and  
unplug. If output voltage is not  
present change Control PCB  
2. Perform the Chopper Board  
Test.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
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F-7  
F-7  
TROUBLESHOOTING & REPAIR  
TROUBLESHOOTING GUIDE  
Observe Safety Guidelines  
detailed in the beginning of this manual.  
PROBLEMS  
(SYMPTOMS)  
POSSIBLE AREAS OF  
MISADJUSTMENT(S)  
RECOMMENDED  
COURSE OF ACTION  
FUNCTION PROBLEMS  
No control of arc voltage. Wire 1. The arc voltage encoder may be 1. The arc voltage encoder may be  
feeding is normal.  
dirty. Rotate several times and  
check if problem is resolved.  
faulty. Codes 10562 have both  
Encoders on one board. Codes  
above 10562 have single  
Encoders.  
2. If machine has code 10562 or  
lower change Encoder Board. If  
machine has Code above 10562  
Perform Encoder Test.  
3. Perform the Chopper Board  
Test.  
4. The Control board may be faulty.  
Replace.  
There is no gas flow when gun trig- 1. Check gas source and hoses for 1. Check for 6.5 VDC when trigger  
ger is pulled. Wire feeds and weld  
voltage is present.  
leaks or kinks.  
is pulled at feedhead Board, Plug  
J83-3 lead 833 and J83-4 lead  
834. See Wiring Diagram.  
2. Check regulator on the tank for  
the pressure being set to high.  
If you read 12 VDC solenoid may  
be open or a bad connection.  
Check wiring.  
Check the gas solenoid by discon-  
necting it from the Feeder Board  
(Plug J83-3 & 4) and applying a 12  
VDC external supply to the gas  
solenoid. If the solenoid does NOT  
activate then it may be faulty.  
Replace.  
2. If 6.5VDc is not present the  
Feeder broad may be faulty.  
Replace.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
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F-8  
F-8  
TROUBLESHOOTING & REPAIR  
Observe Safety Guidelines  
detailed in the beginning of this manual.  
TROUBLESHOOTING GUIDE  
PROBLEMS  
POSSIBLE AREAS OF  
RECOMMENDED  
(SYMPTOMS)  
MISADJUSTMENT(S)  
COURSE OF ACTION  
WIRE FEEDING PROBLEMS  
No control of wire feed speed. 1. The wire feed speed encoder 1. Perform the Wire Drive Motor  
Other machine functions are nor-  
mal.  
control may be dirty. Rotate sev-  
eral times and check if problem  
is resolved.  
and Tachometer Feedback  
Test.  
2. The Wire Speed Encoder may  
be faulty. If code is 10562 or  
below change Encoder PCB. If  
code is above 10562 Perform  
Encoder Test  
3. The Feeder Head Board may be  
faulty. Replace.  
There is no wire feed when gun 1. Check for wire jam at drive rolls. 1. Perform the Wire Drive Motor  
trigger is pulled. Normal open cir-  
cuit voltage is present.  
and Tachometer Feedback  
Test.  
2. If the drive rolls are turning then  
check for a mechanical restric-  
tion in the wire feed path.  
2. The Wire Speed Control  
Encoder may be faulty. If code is  
10562 and below change  
Encoder PCB. If code is above  
10562 Perform Encoder Test  
3. The gun liner may be clogged.  
Check or replace.  
3. The Feeder Head Board may be  
faulty. Replace.  
The machine stops feeding wire 1. Check for adequate wire supply. 1. Check the motor armature cur-  
while welding.  
rent. Normal armature current is  
2.0 to 2.7 amps maximum. If the  
motor armature current is normal  
the Feeder Board may be faulty.  
Replace.  
2. Check for mechanical restric-  
tions in the wire feeding path.  
The gun may be clogged.  
3. Make sure the gun liner and tip  
are correct for wire size being 2. If the motor armature current is  
used.  
high (over 2.7 amps) and there  
are NO restrictions in the wire  
feeding path then the motor or  
gear box may be defective.  
Replace.  
4. Check spindle for ease of rota-  
tion.  
5. Check to see if the spot timer  
has been activated.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
POWER MIG 300  
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F-9  
F-9  
TROUBLESHOOTING & REPAIR  
TROUBLESHOOTING GUIDE  
Observe Safety Guidelines  
detailed in the beginning of this manual.  
PROBLEMS  
(SYMPTOMS)  
POSSIBLE AREAS OF  
MISADJUSTMENT(S)  
RECOMMENDED  
COURSE OF ACTION  
WELDING PROBLEMS  
The arc is unstable and or “hunt- 1. Check for worn or melted contact 1. Check for loose connections at  
ing.”  
tip.  
the output terminals, the chokes,  
and all heavy current carrying  
2. Check for loose or faulty connec-  
tions on the work and electrode  
cables.  
leads.  
Diagram.  
See  
the  
Machine  
2. Make sure that the transformer  
secondary leads are securely  
connected to the Output Rectifier  
assembly.  
3. Make sure electrode polarity or  
welding process being used is  
correct.  
4. Check for rusty or dirty wire.  
3. Check the Output Voltage  
Waveforms. If waveforms are  
not correct Perform the Output  
Rectifier Assembly Tests.  
5. Make sure machine settings are  
correct for process being used.  
(shielding gas, wire type, wire  
size).  
4. Reload latest software. Contact  
a Lincoln Electric sales repre-  
sentative for latest software.  
5. The Control board may be faulty.  
Replace.  
Weld bead is narrow or ropy. May 1. Make sure the weld procedure 1. Check the Output Voltage  
have porosity with electrode stub-  
bing into plate.  
and electrode polarity is correct  
for the process being used.  
Welding voltage may be too low  
for wire feed speed being used.  
Waveforms. If waveforms are  
not correct Perform the Output  
Rectifier Assembly Tests.  
2. Reload latest software. Contact  
a Lincoln Electric sales repre-  
sentative for latest software.  
2. Make sure shielding gas is cor-  
rect and flow is proper.  
3. Make sure the weld joint is not 3. The Control board may be faulty.  
“contaminated”. Replace.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
POWER MIG 300  
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F-10  
F-10  
TROUBLESHOOTING & REPAIR  
Observe Safety Guidelines  
detailed in the beginning of this manual.  
TROUBLESHOOTING GUIDE  
PROBLEMS  
POSSIBLE AREAS OF  
RECOMMENDED  
(SYMPTOMS)  
MISADJUSTMENT(S)  
COURSE OF ACTION  
WELDING PROBLEMS  
The contact tip seizes in the gas dif- 1. The tip being over heated due to 1. Check the Output Voltage  
fuser.  
excessive current and/or high  
duty cycle welding.  
Waveforms.  
2. A light application of high temper-  
ature anti-seize lubricant (such as  
Lincoln E2607 Graphite Grease)  
may be applied to the contact tip  
threads.  
The welding arc is variable and 1. Check the welding cable connec- 1. Check the OCV and Output  
sluggish.  
tions for loose or faulty connec-  
tions.  
Voltage Waverforms. If wave-  
forms are not correct Perform the  
Output Rectifier Assembly  
Tests.  
2. Make sure the wire feed speed,  
voltage, and shielding gas are  
correct for the process being 2. Reload latest software from a  
used.  
Lincoln Electric sales representa-  
tive  
3. The Control Board may be faulty.  
Replace.  
The arc striking is poor.  
1. Check the welding cable connec- 1. Check the Output Voltage  
tions for loose or faulty connec-  
tions.  
Waveforms. If waveforms are  
not correct Perform the Output  
Rectifier Assembly Tests.  
2. Make sure the wire feed speed,  
voltage, and shielding gas are 2. Reload latest software from a  
correct for the process being  
used.  
Lincoln Electric sales representa-  
tive  
3. Run in settings may need to be 3. The Control board may be faulty.  
adjusted. Replace.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
POWER MIG 300  
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F-11  
F-11  
TROUBLESHOOTING & REPAIR  
Observe Safety Guidelines  
TROUBLESHOOTING GUIDE  
detailed in the beginning of this manual.  
FAULT CODES  
SERVICE FACILITY  
CORRECTIVE ACTION  
DESCRIPTION /  
DEFINITION  
CORRECTIVE  
ACTION  
WELDING PROBLEMS  
Glitch on the primary over Check the machine  
Check input cord for cuts  
or marks. Check input  
cord connections at  
reconnect panel.  
39  
44  
current fault interrupt;  
possibly caused by noise  
or a signal level.  
ground. Check for cuts  
or marks on input cord.  
Main CPU problem. The  
Check the machine  
Check input cord for cuts  
or marks. Check input  
cord connections at  
DSP has detected a prob- ground. Check for cuts  
lem with the CPU.  
or marks on input cord.  
reconnect panel. If still  
bad replace Control PCB.  
47  
81  
Glitch on the CAP/heart  
beat interrupt; possibly  
caused by noise or a sig-  
nal level right at the trip  
threshold.  
Turn machine off and let  
sit for 60 second and then If still bad replace Control  
turn back on .  
Run Scrolling dash Test.  
PCB.  
Motor overload-average  
motor current exceeded  
8.00 amps for more than  
0.50 seconds.  
Verify motor armature is  
not binding. Verify wire  
spool is not binding.  
Check current at drive  
motor exceeds 8 amps  
change drive motor. If  
under 8 amps for 0.50  
seconds change Feeder  
Board.  
82  
Motor over current-aver-  
age motor current  
exceeded 3.50 amps for  
more than 10.0 seconds.  
Verify motor armature is  
not binding. Verify wire  
spool is not binding.  
Check current at drive  
motor exceeds 3.50amps  
for 10.0 seconds change  
drive motor.  
214  
Feed Head Board can’t  
be found.  
Turn the machine off and  
back on to reset the  
Using machine schematic  
Check LED 8 on Control  
machine. If condition per- Bd. If not on, check for  
sists, contact and autho-  
rized Lincoln Field  
Service Facility.  
+5VDC at leads 1103 &  
1104. If LED 8 is on  
check for 42VDC at Feed  
Head Bd. If there, Feed  
Head Bd. may be faulty.  
7135  
7138  
MSP can’t be found.  
Turn the machine off and  
back on to reset the  
machine.  
Check for bad connec-  
tions at MSP panel.  
The MSP panel may be  
faulty. Replace.  
Check for bad connec-  
tions at Display Board.  
The Display Board may  
be faulty. Replace.  
Display Board can’t be  
found.  
Turn the machine off and  
back on to reset the  
machine.  
---------  
Scrolling dashes  
Perform Clear all test.  
Perform Clear all test.  
CAUTION  
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely,  
contact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call  
1-800-833-9353.  
POWER MIG 300  
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F-12  
F-12  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD CAPACITOR DISCHARGE PROCEDURE  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician  
or machine operator and will invalidate your factory warranty. For your safety and to avoid  
electrical shock, please observe all safety notes and precautions detailed throughout this  
manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical trou-  
bleshooting assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
This procedure will insure that the five large capacitors on the Chopper Board have been  
discharged. This procedure should be performed whenever work is to be attempted on or  
near the Chopper Board.  
MATERIALS NEEDED  
3/8 in. Nutdriver  
Volt/Ohmmeter  
Resistor (25 ohms and 25 watts minimum)  
Jumper leads  
Wiring Diagram  
POWER MIG 300  
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F-13  
F-13  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD CAPACITOR DISCHARGE PROCEDURE (continued)  
FIGURE F.1 – CHOPPER BOARD CAPACITOR TERMINAL DISCHARGE  
300 CHOPPER  
_
B1  
B4  
C11  
C8  
+
+
+
+
B1  
B4  
C2  
_
B2  
B5  
_
B2  
B5  
B6  
C10  
C9  
+
C12  
_
B3  
B6  
B3  
J99  
5. Using the resistor and jumper leads, CAREFULLY  
discharge the capacitor terminals. There are 5  
capacitors. NEVER USE A SHORTING STRAP  
FOR THIS PURPOSE. DO NOT TOUCH THE  
TERMINALS WITH YOUR BARE HANDS.  
PROCEDURE  
WARNING  
ELECTRIC SHOCK can kill.  
To discharge the capacitors, hold the jumper leads to  
the following terminals for a minimum of 10 seconds  
each. See Figure F.1 and the Wiring Diagram.  
High voltage is present when input power is applied to  
the machine.  
Refer to Figure F.1.  
Capacitors  
Terminals  
1. Remove main input power supply to the machine.  
2. Lift the hinged right side case cover.  
C10 and C11  
B1 and B2  
C5  
B1 and B5  
B4 and B5  
3. Using the 3/8 in. nutdriver, remove the bottom right  
case cover.  
C8 and C9  
4. Locate the Chopper Board with capacitors mount-  
ed on the center of the machine base, right side.  
See Figure F.1.  
6. Using the volt/ohmmeter, check the voltage across  
terminals B1 and B2 and B1 and B5 and B4 and  
B5. Each reading should now be zero volts.  
POWER MIG 300  
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F-14  
F-14  
TROUBLESHOOTING & REPAIR  
MAIN TRANSFORMER TEST  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician  
or machine operator and will invalidate your factory warranty. For your safety and to avoid  
electrical shock, please observe all safety notes and precautions detailed throughout this  
manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical trou-  
bleshooting assistance before you proceed. Call 1-800-833-9353 (WELD).  
TEST DESCRIPTION  
This test will determine if the correct voltages are being applied to the primary windings  
of the main transformer and induced on the secondary and auxiliary windings.  
MATERIALS NEEDED  
3/8 in. Nutdriver  
5/16 in. Nutdriver  
Volt/Ohmmeter  
POWER MIG 300  
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F-15  
F-15  
TROUBLESHOOTING & REPAIR  
MAIN TRANSFORMER TEST (continued)  
FIGURE F.2 – MAIN TRANSFORMER TEST POINT LOCATIONS  
LOCATED ON FRONT  
OF MACHINE'S BASE  
MAIN  
TRANSFORMER  
H1  
LOCATED ON  
MACHINE'S BASE  
(STORAGE  
H5 H2 H3 H4  
H1  
COMPARTMENT SIDE)  
(SHOWN  
CONNECTED  
FOR 230V)  
L1  
L2  
OUTPUT  
LOCATED NEXT TO  
MAIN TRANSFORMER  
(ON WIRE DRIVE SIDE)  
RECTIFIER  
H2  
L1  
L2  
LINE  
SWITCH  
X1  
57 VAC  
X2  
H5  
H3  
RECONNECT PANEL  
H4  
2520  
H1  
s
s
m
t
t
h
a
80 VDC  
o
R1  
w
0
W
B
H1  
H1  
0
0
5
5
2400/100  
-
2530  
H4  
G
H4  
115 VAC 30 VAC  
LOCATED ON  
CHOPPER BOARD  
ASSEMBLY  
X5 X6  
X3 X4  
CONTROL RECTIFIER  
LOCATED ON  
TRANSFORMER  
BAFFLE  
-
5. Test for correct input voltage between L1 lead at the  
LINE SWITCH to L2. Voltage tested will vary  
depending on the input voltage connection. See  
Wiring diagram for test point locations.  
PROCEDURE  
WARNING  
The ON/OFF POWER SWITCH will be "hot" during  
these tests.  
* If the voltage is incorrect, check for loose or broken  
leads between the reconnect panel and the ON/OFF  
POWER SWITCH. Also, test the ON/OFF POWER  
SWITCH for proper operation.  
NOTE: Secondary voltages will vary proportionately  
with the primary input voltage.  
* If the voltage is correct, check for the same voltage  
at H1 and H4 and at the bottom of the LINE  
SWITCH with the switch in the ON position.  
1. Disconnect the main input power supply to the  
machine.  
2. Perform the Case Cover Removal procedure.  
* If the voltage is incorrect, check for loose or broken  
leads between the reconnect panel and the LINE  
SWITCH.  
3. Remove the tool tray with a 5/16 in. nut-driver (3  
screws).  
* If the correct voltage is being applied to the main  
transformer primary winding, proceed to the table  
below for the secondary winding output voltage  
tests.  
TEST INPUT VOLTAGE TO THE MAIN TRANS-  
FORMER PRIMARY WINDING:  
Leads  
X1-X2  
X3-X4  
Description  
Expected Voltage  
57 VAC  
4. Confirm the reconnect panel is connected properly  
for the correct voltage. See reconnect panel con-  
nection diagram located on back of machine above  
reconnect door.  
Power to output  
rectifier  
Power to fan motor  
115 VAC  
Power to control  
rectifier  
X5-X6  
30 VAC  
If the correct voltage is being applied to the main  
transformer and one or more of the secondary volt-  
ages is missing or incorrect, the main transformer  
may be faulty. Replace the main transformer.  
POWER MIG 300  
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F-16  
F-16  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD TEST  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician  
or machine operator and will invalidate your factory warranty. For your safety and to avoid  
electrical shock, please observe all safety notes and precautions detailed throughout this  
manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical trou-  
bleshooting assistance before you proceed. Call 1-800-833-9353 (WELD).  
TEST DESCRIPTION  
This test will help determine if the power module IGBT on the Chopper Board is shorted.  
This test will also check for input voltage and if the PWM signal is present to activate the  
IGBT. It will also determine if the Chopper Board is receiving the correct input voltages.  
MATERIALS NEEDED  
Volt/Ohmmeter (Analog)  
3/8" Socket wrench and 6” extension  
7/16" Nut driver  
POWER MIG 300  
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F-17  
F-17  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD TEST (continued)  
TEST PROCEDURE  
EXPECTED  
VOLTAGE  
TO  
LEAD  
FROM  
LEAD  
1. Disconnect the main AC input power to the  
machine.  
437+(1J99)  
431-(4J99)  
20VDC  
2. Remove the case side panels with a 3/8 in. nutdriv-  
er.  
If 20 VDC is not present check Digital Power Supply.  
See the Wiring Diagram.  
3. Locate plug J99. (Later machine do not have J99).  
4. Make the following voltage test. From the table  
below.  
RESISTANCE TEST  
1. Perform the Capacitor Discharge Procedure.  
5. Turn the machine off between each test:  
2. Remove input power to the machine.  
a. Carefully insert the meter probes into the back of  
each Molex plug cavity.  
3. Perform the resistance tests in Table F.1.  
TABLE F.1– CHOPPER BOARD RESISTANCE TEST TABLE  
Test Point  
B5(+)  
B6(+)  
B4(+)  
B5(+)  
B4(+)  
B6(+)  
B2(+)  
B3(+)  
B4(+)  
B2(+)  
B4(+)  
B3(+)  
Test Point  
Expected Reading  
6 K ohms - 9K ohms  
6 K ohms - 9K ohms  
200 K ohms or Higher  
400 K ohms or Higher  
200 K ohms or Higher  
400 K ohms or Higher  
6 K ohms - 9K ohms  
6 K ohms - 9K ohms  
200 K ohms or Higher  
400 K ohms or Higher  
200 K ohms or Higher  
400 K ohms or Higher  
B6(-)  
B5(-)  
B5(-)  
B4(-)  
B6(-)  
B4(-)  
B3(-)  
B2(-)  
B2(-)  
B4(-)  
B3(-)  
B4(-)  
FIGURE F.3 – CHOPPER BOARD CONNECTIONS  
300 CHOPPER  
_
B1  
B4  
C11  
C8  
+
+
+
+
B1  
B4  
C2  
_
B2  
B5  
_
B2  
B5  
B6  
C10  
C9  
+
C12  
_
B3  
B6  
B3  
J99  
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F-18  
F-18  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD TEST (continued)  
FIGURE F.4  
J6  
J6  
607  
615  
L11088-1  
PWM SIGNAL TEST  
1. Locate 607 (7J6) and 615 (15J6) on the control  
board. See Figure F.4.  
2. Perform the following voltage test or hertz read-  
ings when the trigger is pulled.  
Expected Voltage  
To Lead  
From Lead  
607  
(7J6)  
615  
(15J6)  
1.8-2 VDC  
20 KHZ  
POWER MIG 300  
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F-19  
F-19  
TROUBLESHOOTING & REPAIR  
CONTROL RECTIFIER TEST  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
This test will determine if the correct AC voltages are being applied to the Rectifier Diode  
Bridge and supplied from the Rectifier Diode Bridge to the Digital Power Supply board.  
MATERIALS NEEDED  
Volt/Ohmmeter  
3/8" Nut driver  
POWER MIG 300 Machine Schematic  
POWER MIG 300  
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F-20  
F-20  
TROUBLESHOOTING & REPAIR  
CONTROL RECTIFIER TEST (continued)  
FIGURE F.5  
115 VAC 30 VAC  
X5 X6  
X3 X4  
CONTROL RECTIFIER  
LOCATED ON  
TRANSFORMER  
-
FAN  
BAFFLE  
+ 42VDC  
+
6800/75  
2. Carefully connect the meter probes to the exposed  
lead connections.  
TEST PROCEDURE  
1. Find the following leads at the control rectifier using  
figures F.5 and F.6.  
3. Turn the machine ON to conduct the voltage test.  
Expected Voltage  
From Lead  
471B  
To Lead  
472B  
X6  
42 VDC  
30 VAC  
4. If the DC voltage tested is incorrect or missing, and  
the AC voltages are correct, the control rectifier  
bridge or capacitor may be faulty.  
X5  
FIGURE F.6  
CONTROL RECTIFIER  
POWER MIG 300  
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F-21  
F-21  
TROUBLESHOOTING & REPAIR  
OUTPUT RECTIFIER ASSEMBLY TEST  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician  
or machine operator and will invalidate your factory warranty. For your safety and to avoid  
electrical shock, please observe all safety notes and precautions detailed throughout this  
manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical trou-  
bleshooting assistance before you proceed. Call 1-800-833-9353 (WELD).  
TEST DESCRIPTION  
This test will determine if the Output Rectifier is shorted. See the Oscilloscope  
Waveforms section of this manual for normal and abnormal output waveforms.  
MATERIALS NEEDED  
Analog Volt/Ohmmeter (If Digital Meter is used you must use in diode check mode.  
Do not use ohms scale)  
3/8” Nutdriver  
5/16” Nutdriver  
1/2” Wrench  
Power MIG 300 Wiring Diagram (See the Machine Schematic in this manual)  
POWER MIG 300  
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F-22  
F-22  
TROUBLESHOOTING & REPAIR  
OUTPUT RECTIFIER ASSEMBLY TEST (continued)  
FIGURE F.7– OUTPUT RECTIFIER ASSEMBLY LOCATION  
+
-
Negative Lead  
A A  
B B  
TEST PROCEDURE  
5. If any of the diodes are leaky or shorted the output  
rectifier assembly should be replaced.  
1. Disconnect the main AC input power to the  
machine.  
6. When the test is complete, replace the negative out-  
put previously removed.  
2. Perform the Chopper Assembly Capacitor  
Discharge procedure.  
7. Replace case side.  
3. Locate and disconnect the negative lead from the  
output rectifier bridge assembly.  
NOTE: Do not disassemble the rectifier assembly.  
4. Test for shorted or leaky diodes by checking from  
the outside plate (A) to inside plate (A) then reverse  
your leads and recheck the same plates. Do the  
same to plate B. The readings should be high resis-  
tance in one polarity and low resistance in the oppo-  
site polarity. See Figure F.7.  
POWER MIG 300  
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F-23  
F-23  
TROUBLESHOOTING & REPAIR  
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK  
TEST  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician  
or machine operator and will invalidate your factory warranty. For your safety and to avoid  
electrical shock, please observe all safety notes and precautions detailed throughout this  
manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical trou-  
bleshooting assistance before you proceed. Call 1-800-833-9353 (WELD).  
TEST DESCRIPTION  
This test will determine if the wire drive motor and voltage feedback circuits are function-  
ing properly.  
MATERIALS NEEDED  
5/16" Nutdriver  
Volt/Ohmmeter  
POWER MIG 300  
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F-24  
F-24  
TROUBLESHOOTING & REPAIR  
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST (continued)  
FIGURE F. 8 – PLUG J83 AND J84 LOCATIONS ON FEEDER BOARD  
TOROID  
MOTOR +  
1
2
1J83  
2J83  
3J83  
4J83  
831  
832  
833  
834  
MOTOR -  
GAS SOLENOID+  
GAS SOLENOID -  
G3884  
PWM CONTROLLED  
6.5 VDCWHENGAS  
FLOWING COIL  
LOCATED ON  
CASE BACK  
MEASURES 21 OHMS  
12 VDC COIL  
B
W
ACCESS THIS CONNECTOR  
BY REMOVINGTHEWIRE  
DRIVE ASSEMBLY  
TOROID  
MOTOR / GEARBOX  
TACH  
5VDC TACH SUPPLY  
2.6 VDC@ 50 IN/MIN  
R
U
B
R
U
B
1
841  
847  
844  
1J84  
7J84  
4J84  
TACH SIGNAL  
TACHCOM  
27.4 VDC@ 700 IN/MIN  
8 SECOND AVERAGE CURRENT  
LIMIT = 3.5A  
2
J83  
J84  
3
4
MEASURE B TO U  
120 Hz @ 50 IN/MIN  
(LIMIT IS SOFTWARE SET)  
1.6 kHz@700 IN/MIN  
J84  
J83  
844  
841  
847  
832  
831  
5. Connect the main power to the machine.  
TEST PROCEDURE  
NOTE: POLARITY MUST BE OBSERVED FOR  
7. Make the following voltage tests. From the table  
below.  
THESE TESTS.  
TEST FOR CORRECT WIRE DRIVE MOTOR  
ARMATURE VOLTAGE  
8. Carefully insert the meter probes into the back of  
each Molex plug pin cavity to perform the test.  
1. Disconnect main input power to the machine.  
9. Turn the machine ON and pull the gun trigger to  
conduct this voltage test.  
2. Open the side panels and remove the tool tray  
using a 5/16 in. nutdriver.  
3. Locate the following leads on plug J83:  
4. Locate leads 831(black) and 832(white) on plug  
J83.  
FROM LEAD TO LEAD EXPECTED VOLTAGE  
831 +  
832 -  
2.5-27 VDC  
(1J83)  
(2J83)  
(varies depending  
on wire feed speed)  
POWER MIG 300  
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F-25  
F-25  
TROUBLESHOOTING & REPAIR  
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST (continued)  
TEST FOR SUPPLY VOLTAGE TO  
TACHOMETER AND FEEDBACK VOLTAGE  
FROM LEAD TO LEAD EXPECTED VOLTAGE  
847 +  
(7J84)  
844 -  
(4J84)  
1. Locate the following leads on Plug J84. Leads 841  
(1J84) and 844 (4J84)  
1.5 to 3.5 VDC  
2. Make the following voltage tests. From the table  
below.  
10. If the 1.5 to 3.5 VDC is not present or not correct,  
the Feeder Board is not receiving the proper feed-  
back voltage from the tachometer circuit. Check the  
leads from the tachometer circuit to the Feeder  
Board for loose or broken connections.  
3. Turn the machine OFF between each test.  
4. Carefully insert the meter probes into the back of  
each Molex plug pin cavity. This is the tach supply  
voltage.  
11. If the leads are okay, the tachometer circuit may be  
faulty, replace the tach Sensor.  
FROM LEAD TO LEAD EXPECTED VOLTAGE  
841 +  
844 -  
5 VDC  
(1J84)  
(4J84)  
5. If the 5 VDC is present, go to next step. If no volt-  
age is measured Feeder Head Board may be bad.  
Check connections back to Feed Head Board.  
6. Locate the leads on Plug J84 noted in the table  
below.  
7. Carefully insert the meter probes into the back of  
each Molex plug pin cavity  
8. Turn the machine ON and pull the gun trigger to  
conduct the voltage test.  
9. If the 1.5 to 3.5 VDC is present, the tachometer  
circuit is sending the correct feedback signal to the  
Feeder Board. Replace the Feeder Board.  
POWER MIG 300  
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F-26  
F-26  
TROUBLESHOOTING & REPAIR  
ENCODER PC BOARD TEST  
(FOR CODES ABOVE 10562)  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
This test will help determine if the encoders are functioning properly for machines above code  
10562 only.  
MATERIALS NEEDED  
Volt/Ohmmeter (analog recommended)  
5/16" Nut driver  
POWER MIG 300  
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F-27  
F-27  
TROUBLESHOOTING & REPAIR  
ENCODER PC BOARD TEST (continued)  
FIGURE F. 9 - FEEDHEAD P.C. BOARD  
G3884  
J82  
3243  
J85  
TEST PROCEDURE  
1. Disconnect the main AC input power to the  
machine.  
5. Turn the machine OFF between each test.  
6. Carefully insert the meter probes into the back of  
each Molex plug pin cavity.  
2. Locate the following leads on Plug J85 and J86  
located on the feedhead P.C. Board. See Figure  
F.9.  
7. As you turn the encoder slowly the voltage will  
change from zero to15 volts to zero, to 15 volts etc.  
as you continue to turn the encoder.  
3. Connect main input power to the machine.  
4. Make the following voltage tests. From the tables  
on following page.  
POWER MIG 300  
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F-28  
F-28  
TROUBLESHOOTING & REPAIR  
ENCODER PC BOARD TEST (continued)  
VOLT/TRIM ENCODER #1  
FROM LEAD TO LEAD EXPECTED VOLTAGE  
ACTION  
If you do not read 15VDC on the first reading of encoder  
#1 or #2 then check lead connections. If lead connec-  
tions check OK, then Feeder Board may be faulty,  
replace Feeder Board.  
855  
5J85  
3243  
3J82  
15 VDC  
8511  
11J85  
3243  
3J82  
0 OR 15 VDC  
0 OR 15 VDC  
As you turn the encoder #1 or #2 slowly you should see  
your meter go from 0 to 15, 0 to 15 as you turn the  
encoder. If not, check the lead connections. If the lead  
connection check OK then, change the encoder.  
858  
8J85  
3243  
3J82  
WMF/AMPS ENCODER #2  
FROM LEAD TO LEAD EXPECTED VOLTAGE  
ACTION  
If you do not read 15VDC on the first reading of encoder  
#1 or #2 then check lead connections. If lead connec-  
tions check OK, then Feeder Board may be faulty,  
replace Feeder Board.  
859  
9J85  
3243  
3J82  
15 VDC  
857  
7J85  
3243  
3J82  
0 OR 15 VDC  
As you turn the encoder #1 or #2 slowly you should see  
your meter go from 0 to 15, 0 to 15 as you turn the  
encoder. If not, check the lead connections. If the lead  
connection check OK then, change the encoder.  
POWER MIG 300  
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F-29  
F-29  
TROUBLESHOOTING & REPAIR  
CURRENT TRANSDUCER TEST  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
This test will determine if the current transducer and associated wiring are functioning cor-  
rectly.  
MATERIALS NEEDED  
Volt/Ohmmeter  
3/8" Nut driver  
POWER MIG 300  
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F-30  
F-30  
TROUBLESHOOTING & REPAIR  
CURRENT TRANSDUCER TEST (continued)  
FIGURE F.10  
J8  
L11088-1  
8. If excepted voltages are not present the Control  
Board may be faulty.  
TEST PROCEDURE  
1. Remove input power to the machine  
9. Check the feedback voltage from the current  
transducer with the Power Mig set on Mode 1 or 2  
and the machine loaded to 250 amps.  
2. Remove the left case side of the machine.  
3. Remove the PC compartment door.  
10. Make the following voltage test. From the table  
below.  
4. Locate plug J8 at the Control Board. See Figure  
F.10.  
11. If the measured feedback voltage is not correct for  
the output load current. The current transducer  
may be faulty.  
5. Connect the main power to the machine.  
6. Make the following voltage test. From the table  
FROM LEAD TO LEAD EXPECTED VOLTAGE  
below. Also see Table F.2.  
801  
806  
2.0 VDC  
(1J8)  
(6J8)  
7. Carefully insert the meter probes into the back of  
each Molex plug pin cavity.  
12. If for any reason the machine cannot be loaded to  
250 amps, Table F.2 shows what feedback volt-  
age is produced at various current loads.  
FROM LEAD TO LEAD EXPECTED VOLTAGE  
802+  
(2J8)  
806-  
(6J8)  
+15 VDC  
POWER MIG 300  
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F-31  
F-31  
TROUBLESHOOTING & REPAIR  
CURRENT TRANSDUCER TEST (continued)  
TABLE F.2 – CURRENT TRANSDUCER FEEDBACK VOLTAGE  
EXPECTED TRANSDUCER  
OUTPUT LOAD CURRENT  
FEEDBACK VOLTAGE  
500  
450  
400  
350  
300  
250  
200  
150  
100  
4.0  
3.6  
3.2  
2.8  
2.4  
2.0  
1.6  
1.2  
0.8  
POWER MIG 300  
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F-32  
F-32  
TROUBLESHOOTING & REPAIR  
POWER MIG 300 SCROLLING DASHES TEST  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
ERROR CODE: Scrolling dashes on the POWER MIG 300 perform the appropriate clear all  
procedure as follows.  
MATERIALS NEEDED  
None  
POWER MIG 300  
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F-33  
F-33  
TROUBLESHOOTING & REPAIR  
POWER MIG 300 SCROLLING DASHES TEST (continued)  
TEST PROCEDURES:  
For Machines with code 10562.  
For Machines with code 10952, 10958  
and 11000.  
1. Hold “select” switch up while powering up  
machine.  
1. Hold “select” switch up while powering up  
machine.  
2. Continue to hold “select” switch up and turn  
right “encoder” until display reads “CLrAll”.  
2. Release “select” switch when displays show  
“PrESSPin”.  
3. Release the “select” switch.  
4. Machine will reset itself.  
3. Turn the right “encoder knob” until displays  
show “CLrAll”.  
4. Toggle the “select” switch up and release.  
5. Machine will reset itself.  
POWER MIG 300  
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F-34  
F-34  
TROUBLESHOOTING & REPAIR  
OSCILLOSCOPE WAVEFORMS MUST BE TAKEN IN MODE 201  
NORMAL OPEN CIRCUIT VOLTAGE WAVEFORM  
2.0 MS/DIV  
This is a typical DC output voltage waveform generated from a properly operating machine. Note that  
20.0 V  
each vertical division represents 20 volts and that each horizontal division represents 2.00 milliseconds in  
time.  
NOTE: Scope probes connected at the machine output terminals: (+) probe to electrode, (-) probe to work.  
SCOPE SETTINGS  
Volts/Div.....................20V/Div.  
Horizontal Sweep..2.5 ms/Div.  
Coupling.............................DC  
Trigger.........................Internal  
CODES 10562 AND BELOW  
CODES 10952 AND UP  
Power Mig 300 in mode 201. Mode 201 is a con-  
stant current test mode.  
Power Mig 300 in mode 201. Mode 201 is a con-  
stant current test mode.  
1. Toggle and hold the Mode Select switch in the up  
position.  
1. Toggle and hold the Mode Select switch in the up  
position.  
2. Turn on the Power Mig 300.  
2. Turn on the Power Mig 300.  
3. Rotate the right output knob, while still holding the  
Mode Select switch up, until the display reads  
“ALL nodE”.  
3. Once the display reads “Pres Spin” release the  
mode select switch. Rotate the output knob until  
the display reads “ALL nodE”.  
4. Release the Mode Select switch and toggle the  
Mode Set switch until the MSPlll panel reads 201.  
Disengage the idler arm on the wire drive so no  
wire will feed.  
4. Toggle the Mode Select switch once and wait for  
the machine to reset, then toggle the MODE SET  
switch until the MSPlll panel reads 201. Disengage  
the idler arm on the wire drive so no wire will feed.  
POWER MIG 300  
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F-35  
F-35  
TROUBLESHOOTING & REPAIR  
TYPICAL OUTPUT VOLTAGE WAVEFORM - MACHINE LOADED  
MACHINE LOADED TO 250 AMPS AT 26 VDC  
2.0 MS/DIV  
20.0 V  
This is a typical DC output voltage waveform generated from a properly operating machine. Note that  
each vertical division represents 20 volts and that each horizontal division represents 2.00 milliseconds in  
time.  
NOTE: Scope probes connected at the machine output terminals: (+) probe to electrode, (-) probe to work.  
SCOPE SETTINGS  
Volts/Div.....................20V/Div.  
Horizontal Sweep.....5 ms/Div.  
Coupling.............................DC  
Trigger.........................Internal  
POWER MIG 300  
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F-36  
F-36  
TROUBLESHOOTING & REPAIR  
MOTOR & GEAR BOX ASSEMBLY REMOVAL AND  
REPLACEMENT  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician  
or machine operator and will invalidate your factory warranty. For your safety and to avoid  
electrical shock, please observe all safety notes and precautions detailed throughout this  
manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical trou-  
bleshooting assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
This test will aid the technician in the removal and replacement of the Motor and Gear box  
assembly.  
MATERIALS NEEDED  
3/8” Nut driver  
5/16 in. Nut driver  
9/16” Wrench  
7/16” Wrench  
Small slot head screwdriver  
Large Phillips head screwdriver  
Pliers  
Wiring Diagram  
POWER MIG 300  
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F-37  
F-37  
TROUBLESHOOTING & REPAIR  
MOTOR & GEAR BOX ASSEMBLY  
REMOVAL AND REPLACEMENT (continued)  
REMOVAL PROCEDURE  
11. Using a Phillips head screwdriver, remove the 3  
pan head screws and lock washers securing the  
motor/gearbox assembly to the wire drive assem-  
bly.  
WARNING  
ELECTRIC SHOCK can kill.  
12. Grasp the motor/gearbox assembly and wiggle it  
gently back and forth until it separates from the  
wire drive assembly.  
High voltage is present when input power is applied to  
the machine.  
13. Using a 5/16 in. nutdriver, remove the 3 screws  
holding the wire drive compartment (with wire drive  
assembly still attached) to the divider panel welded  
assembly. Pull the compartment away. The motor  
and gearbox can now be removed.  
1. Disconnect main input power to the machine.  
2. Remove the wire gun and wire.  
3. Lift the tool tray door to allow access to the tool tray.  
14. Using a 7/16 in. nutdriver, remove the 3 hex head  
cap screws, lock washers, and flat washers secur-  
ing the wire drive assembly to the wire drive com-  
partment.  
4. Using the 5/16 in. nutdriver, remove the tool tray (3  
screws) to gain access to the motor/gearbox  
assembly.  
5. Disconnect motor leads 831 and 832 and tach leads  
841, 844 and 847at their in-line connectors. See  
the Wiring Diagram.  
15. Remove the wire drive assembly from the wire  
drive compartment.  
For Codes 10958 & Above. See Figure F.12.  
6. Using a 9/16 in. wrench, remove the bolt, lock  
washer, flat washer and positive lead from the wire  
drive assembly. Using pliers, remove the hose  
clamp and flex hose from the wire drive assembly.  
(Depends on the type of gun being used).  
10. Using a 9/16 in. wrench to remove nut that holds  
molded drive roll shaft assembly to the wire drive  
assembly. Remove the molded drive roll shaft  
assembly form the wire drive assembly.  
7. Rotate the adjustment arm assembly counterclock-  
wise to release the tension on the idle arm.  
11. Using a 7/16 in. wrench remove panel covering the  
gear.  
8. Swing the idle arm up and away from the wire drive  
assembly.  
12. Using a Phillips head screwdriver remove gear.  
13. Using a Phillips head screwdriver, remove the 3  
pan head screws and lock washers securing the  
motor/gearbox assembly to the wire drive assem-  
bly.  
9. Remove the outer guide assembly from the wire  
drive assembly by loosening the thumb screws  
until the outer guide can be removed. Rotate the  
molded keeper until the ears line up with the slots  
on the drive roll, then pull the drive roll off the shaft  
assembly. Now slide off the inner guide.  
14. Grasp the motor/gearbox assembly and wiggle it  
gently back and forth until it separates from the  
wire drive assembly.  
For Codes 10952 & Below, See Figure F.11.  
15. Using a 3/8 nut driver remove 6 nuts that hold  
cover. Remove panel to expose drive motor.  
10. Using a slotted screwdriver, remove the round  
head screw, lock washer, and flat washer securing  
the lower molded drive roll shaft assembly to the  
wire drive assembly. Remove the molded drive roll  
shaft assembly from the wire drive assembly. It  
may be necessary to GENTLY pry behind the gear  
to get it started off the shaft.  
POWER MIG 300  
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F-38  
F-38  
TROUBLESHOOTING & REPAIR  
MOTOR & GEAR BOX ASSEMBLY  
REMOVAL AND REPLACEMENT (continued)  
REPLACEMENT PROCEDURE  
5. Attach the flex hose and clamp.  
6. Attach the tool tray.  
1. Bolt the wire drive assembly to the wire drive  
compartment.  
2. Secure the wire drive compartment to the  
divider panel welded assembly.  
7. Attach the wire gun and wire.  
3. Mount the motor/gearbox assembly to the wire  
drive assembly and attach with screws.  
4. Assemble the drive roll components to the wire  
drive assembly.  
FIGURE F.11  
FOR CODES BELOW 10952  
4
14  
15  
8
9
13  
12  
5
7
10  
6
11  
POWER MIG 300  
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F-39  
F-39  
TROUBLESHOOTING & REPAIR  
MOTOR & GEAR BOX ASSEMBLY  
REMOVAL AND REPLACEMENT (continued)  
FIGURE F.12  
FOR CODES ABOVE 10958  
8
10  
12  
11  
13  
15  
9
14  
5
6
POWER MIG 300  
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F-40  
F-40  
TROUBLESHOOTING & REPAIR  
OUTPUT RECTIFIER  
REMOVAL AND REPLACEMENT  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
The procedure will aid the technician in the removal and replacement of the output rectifier  
assembly.  
MATERIALS NEEDED  
1/2 in. Open end wrench  
1/2 in. Socket wrench and extension  
3/8 in. Nutdriver  
3/8 in. Open end wrench  
Slot head screwdriver  
Diagonal cutters  
Dow Corning #340 compound  
POWER MIG 300  
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F-41  
F-41  
TROUBLESHOOTING & REPAIR  
OUTPUT RECTIFIER  
REMOVAL AND REPLACEMENT (continued)  
FIGURE F.13  
8
7
5
11  
4
6
9
er terminal marked positive (+) . For reassembly,  
note placement of the fasteners: bolt, flat washer,  
heavy lead, small lead, terminal, flat washer, lock  
washer, nut.  
WARNING  
ELECTRIC SHOCK can kill.  
6. Using a slot head screwdriver and a 3/8 in. wrench,  
remove Resistor R1 from the machine base. This  
will provide additional clearance for accessing fas-  
teners and removing the rectifier. For reassembly,  
note order of the components for the resistor:  
screw, star washer, plastic insulator, resistor, plastic  
insulator. This assembly rests on top of the  
machine base. From beneath the base a flat wash-  
er, lock washer, and nut attach to the screw. It is a  
good practice to loosely assemble the parts and set  
the resistor aside until ready to be reassembled.  
High voltage is present when input power is applied to  
the machine.  
NOTE: Cut cable ties as needed to improve access.  
See Figure F.13 for the following procedure.  
1. Disconnect main input power from the machine.  
2. Perform the Chopper Board Capacitor Discharge  
7. Using a 1/2 in. wrench and a 1/2 in. socket wrench  
with extension, remove heavy lead X2 from the ter-  
minal at the top of the rectifier, near side. For  
reassembly, note placement of the fasteners: bolt,  
flat washer, heavy lead, terminal, lock washer, nut.  
Procedure.  
3. Remove the right side panel using a 3/8 in. nutdriv-  
er. (as viewed from the front of machine).  
4. Using the 1/2 in. wrenches, remove heavy lead B1  
and small resistor lead 2530 from the output rectifi-  
er lower terminal, marked negative (-) . For  
reassembly, note placement of the fasteners: bolt,  
flat washer, heavy lead, small lead, terminal, flat  
washer, lock washer, nut.  
8. Using a 1/2 in. wrench and a 1/2 in. socket wrench  
with extension, remove heavy lead X1 (from the  
output choke) from the other terminal at the top of  
the rectifier, nearer to the chopper board assembly.  
For reassembly, note placement of the fasteners:  
bolt, flat washer, heavy lead, terminal, lock washer,  
nut.  
5. Using the 1/2 in. wrenches, remove heavy lead B5  
and small resistor lead 2520 from the output rectifi-  
POWER MIG 300  
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F-42  
F-42  
TROUBLESHOOTING & REPAIR  
OUTPUT RECTIFIER  
REMOVAL AND REPLACEMENT (continued)  
9. Using a 3/8 in. wrench, remove the 4 nuts and lock  
washers holding the rectifier bracket to the machine  
base.  
10. Clear the leads and carefully remove the output  
rectifier assembly.  
11. With a 1/2 in. wrench, loosen the3 nuts holding the  
rectifier to its bracket.  
REPLACEMENT PROCEDURE  
NOTE: When installing the output rectifier assembly,  
apply a thin coating of Dow Corning #340 com-  
pound to the electrical connections.  
1. Fit the new output rectifier into its bracket.  
2. Install the output rectifier. Fasten it to the machine  
base with 4 lock washers and nuts.  
3. Install heavy leads X1 and X2 to the terminals at the  
top of the output rectifier. X1 mounts to the termi-  
nal nearer to the chopper board assembly. Note  
placement of fasteners as described above.  
4. Install resistor R1.  
5. Install heavy lead B5 and resistor lead 2520 to the  
lower terminal, marked (+).  
6. Install heavy lead B1 and resistor lead 2530 to the  
upper terminal, marked (-).  
7. Replace any cable ties removed for disassembly.  
8. Install the case side panels.  
POWER MIG 300  
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F-43  
F-43  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD ASSEMBLY REMOVAL  
AND REPLACEMENT  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
The following procedure will aid the technician in the removal and replacement of the Chopper  
Board assembly. The assembly is replaced as a unit; there are no serviceable parts.  
MATERIALS NEEDED  
5/16 in. Nutdriver  
3/8 in. Nutdriver or wrench  
7/16 in. Open end wrench  
1/2 in. Open end wrench  
1/2 in. Socket wrench, universal tool, and extension  
3/8 in. Nutdriver  
3/8 in. Open end wrench  
Diagonal cutters  
Wiring Diagram  
POWER MIG 300  
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F-44  
F-44  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD ASSEMBLY REMOVAL  
AND REPLACEMENT (continued)  
FIGURE F.14 – CHOPPER BOARD ASSEMBLY DETAILS  
9
12  
8
23D  
10  
7
12  
4
6
Leads B8 & B7  
(other side of chopper board)  
6. Disconnect lead 607 from terminal B8 and lead 613  
from terminal B7 at their in-line connectors.  
REMOVAL PROCEDURE  
WARNING  
7. Using a 7/16 in. wrench, remove heavy lead B8 (to  
negative output terminal) and B2 (to choke) from  
the chopper board.  
ELECTRIC SHOCK can kill.  
High voltage is present when input power is applied to  
the machine.  
8. Using a 7/16 in. wrench, remove heavy leads B1  
and B5 (to output rectifier) from the chopper board.  
9. Using the 5/16 in. nutdriver, remove the 4 screws  
holding the fan baffle to the machine base. This  
will allow you to move the baffle back out of the  
way to access the right rear nut on the chopper  
assembly bracket.  
NOTE: Cut cable ties as needed to improve access.  
See Figure F.14 for the following procedure.  
1. Disconnect main input power from the machine.  
10. Using the 3/8 in. wrench or nutdriver, remove the 4  
nuts holding the chopper assembly brackets to the  
machine base.  
2. Perform the Chopper Board Capacitor Discharge  
Procedure.  
3. Remove the case side panels using a 3/8 in. nut-  
driver.  
11. Carefully remove the chopper assembly from the  
machine.  
4. Label and disconnect thermostat leads 503 and  
503A.  
12. Using a 7/16 in. wrench, remove the 2 support  
brackets from the chopper board assembly.  
5. Unplug J99 from the chopper board.  
POWER MIG 300  
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F-45  
F-45  
TROUBLESHOOTING & REPAIR  
CHOPPER BOARD ASSEMBLY REMOVAL  
AND REPLACEMENT (continued)  
REPLACEMENT PROCEDURE  
1. Attach the chopper assembly brackets to the new  
chopper assembly.  
2. Install the chopper board assembly. Fasten it to the  
machine base with 4 lock washers and nuts.  
3. Install heavy leads B1 and B5.  
4. Install heavy leads B6 and B2.  
5. Connect lead 607 (B8) and lead 613 (B7) at their in-  
line connectors.  
6. Connect plug J99.  
7. Connect thermostat leads 503 and 503A.  
8. Install the case side panels.  
POWER MIG 300  
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F-46  
F-46  
TROUBLESHOOTING & REPAIR  
MAIN TRANSFORMER AND OUTPUT CHOKE REMOVAL AND  
REPLACEMENT  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
The procedure will aid the technician in the removal and replacement of the main trans-  
former and choke assembly.  
MATERIALS NEEDED  
5/16 in. Nutdriver  
3/8 in. Nutdriver or open end wrench  
1/2 in. Open end wrench  
1/2 in. Socket wrench and extension  
9/16 in. Open end wrench  
Diagonal cutters  
Phillips head screwdriver  
POWER MIG 300  
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F-47  
F-47  
TROUBLESHOOTING & REPAIR  
MAIN TRANSFORMER AND OUTPUT CHOKE REMOVAL AND  
REPLACEMENT (continued)  
REMOVAL PROCEDURE  
5. Remove gun.  
WARNING  
6. Remove work lead from output stud.  
CASE FRONT ASSEMBLY REMOVAL  
7. Remove the case front assembly as follows:  
ELECTRIC SHOCK can kill.  
High voltage is present when input power is applied to  
the machine.  
a. Using a phillips head screwdriver, remove the 2  
screws holding the line switch to the case front.  
b. Using a 5/16 in. nutdriver, remove 10 screws hold-  
ing the case front to the to the machine base and  
center assembly.  
NOTE: Cut cable ties as needed to improve access.  
PREPARATION  
c. Lift the case front upward and forward slightly, then  
disconnect plug J34 from the MSP3 mode select  
panel. The case front assembly can now be  
removed. See Figure F.13.  
1. Disconnect main input power from the machine.  
2. Remove the case side panels using a 3/8 in. nut-  
driver.  
3. Perform the Chopper Board Capacitor Discharge  
Procedure.  
4. Remove the case top using a 3/8 in. nutdriver.  
POWER MIG 300  
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F-48  
F-48  
TROUBLESHOOTING & REPAIR  
MAIN TRANSFORMER AND OUTPUT CHOKE REMOVAL AND  
REPLACEMENT (continued)  
assembly can now be lifted enough to allow the  
main transformer and choke assembly to be  
removed.  
LEAD DISCONNECTION  
8. Using a phillips head screwdriver, remove fan lead  
X4 from fan relay terminal #1 and disconnect fan  
lead X3 from its in-line connector at the fan motor.  
Cut cable ties as needed pull the leads through the  
baffles to clear them.  
18. With the help of an assistant, lift the front of the  
center assembly and slide the main transformer  
and choke assembly out through the front of the  
machine. Use care -- the assembly is very heavy.  
9. Using a 1/2 in. wrench, disconnect leads X1 and X2  
from the output rectifier. Note the order of the fas-  
teners for reassembly: bolt, flat washer, heavy  
lead, terminal, lock washer, nut.  
REPLACEMENT PROCEDURE  
For lead reassembly steps, also see the Wiring  
Diagram.  
10. Disconnect leads X5 and X6 from the control recti-  
fier (spade connectors).  
1. With the help of an assistant, carefully slide the new  
transformer/choke assembly into place. Attach it to  
the machine base with 4 bolts, lock washers, and  
nuts.  
11. Disconnect thermostat leads 502 and 503A from  
their in-line connectors (right side of the machine).  
12. Using a 3/8 in. nutdriver, disconnect leads H2, H3,  
and H5 from the reconnect panel terminals 2, 3,  
and 5.  
2. Attach the right and left transformer baffles to the  
machine base (1 screw each side).  
3. Connect the heavy lead from the top of the choke to  
the positive output terminal.  
13. Using a 3/8 in. driver, disconnect leads H1 and H4  
from the back of the line switch. Looking at the  
back of the switch, H1 is at the bottom right and H4  
is at the bottom left. Note that leads H1 and H4,  
which go to the reconnect panel, attach at these  
same terminals.  
4. Connect heavy lead B2 to the choke.  
5. Connect leads H1 and H4 to the back of the line  
switch. See disassembly step for details.  
14. Using a 1/2 in. wrench and socket wrench, discon-  
nect heavy lead B2 from the choke.  
6. Connect leads H2, H3, and H5 to the reconnect  
panel.  
15. Using a 9/16 in. wrench and socket wrench, dis-  
connect the heavy lead from the choke to the pos-  
itive output terminal. It is not necessary to remove  
any other leads; screw the bolt with leads still  
attached back into the positive output terminal until  
reassembly.  
7. Connect thermostat leads 502 and 503A at their in-  
line connectors (right side of the machine).  
8. Connect leads X5 and X6 to the control rectifier  
(spade connectors).  
9. Connect leads X1 and X2 to the output rectifier.  
Note the order of the fasteners: bolt, flat washer,  
heavy lead, terminal, lock washer, nut.  
MAIN TRANSFORMER AND CHOKE  
ASSEMBLY REMOVAL  
10. Connect fan lead X4 to fan relay terminal 1 and fan  
lead X3 at its in line connector at the fan motor.  
16. Using a 1/2 in. socket wrench, remove 4 nuts and  
lock washers that hold the main transformer to the  
machine base. Also remove the 4 in. bolts from  
underneath.  
11. Install the case front assembly. Connect plug J34  
and mount the line switch.  
12. Install new cable ties as needed.  
13. Install the case sides and top.  
17. Using a 5/16 in. nutdriver, remove the 2 screws that  
hold the right and left transformer baffle in place (1  
screw each). The center assembly and rear  
POWER MIG 300  
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F-49  
F-49  
TROUBLESHOOTING & REPAIR  
MAIN TRANSFORMER AND OUTPUT CHOKE REMOVAL AND  
REPLACEMENT (continued)  
FIGURE F.15  
12  
8
7C  
15  
9
BACK  
SIDE  
5
10  
UNDER  
PANEL  
11  
6
14  
7B  
16  
TEN  
(10)  
17  
13  
7A  
BACK  
SIDE  
POWER MIG 300  
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F-50  
F-50  
TROUBLESHOOTING & REPAIR  
FAN MOTOR ASSEMBLY REMOVAL AND REPLACEMENT  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
The procedure will aid the technician in the removal and replacement of the fan motor  
assembly.  
MATERIALS NEEDED  
3/8 in. Nutdriver  
11/32 in. Open end wrench  
Diagonal cutters  
Slot or phillips head screwdriver  
POWER MIG 300  
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F-51  
F-51  
TROUBLESHOOTING & REPAIR  
FAN MOTOR ASSEMBLY REMOVAL AND REPLACEMENT  
(continued)  
FIGURE F.16 – FAN MOTOR ASSEMBLY REMOVAL  
4A  
4B  
6
6
5
6. Remove the fan motor.  
REMOVAL PROCEDURE  
a. Loosen and remove the two nuts and lock wash-  
ers from the motor mounting bracket using a  
11/32 in. open end wrench.  
1. Disconnect main input power to the machine.  
2. Remove the case side panels using a 3/8 in. nut-  
driver.  
b. When the motor is free from the mounting brack-  
et, slide the motor from the POWER MIG unit.  
3. Cut the wire tie from around the fan motor leads.  
4. Disconnect fan motor leads:  
REPLACEMENT PROCEDURE  
a. Unplug the black lead from its in-line connector.  
1. Attach the fan motor to the mounting bracket.  
b. Using a slot or phillips head screw driver, dis-  
connect the white lead at the fan relay. See  
Figure F.16.  
2. Install the fan blade and tighten the fan blade  
clamp. Ensure the fan is in the same position on  
the shaft as it was prior to removal. Spin the fan to  
be sure it is free to rotate.  
5. Remove the fan blade. Note the position of the fan  
on the shaft for reassembly.  
3. Connect the fan motor leads: black at its in-line con-  
nector and white at fan relay terminal 1.  
a. Using a slot head screwdriver, loosen the fan  
blade clamp.  
4. Install the case sides.  
b. Slide the fan blade off the motor shaft.  
POWER MIG 300  
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F-52  
F-52  
TROUBLESHOOTING & REPAIR  
VOLTAGE & CURRENT CALIBRATION PROCEDURE  
WARNING  
Service and repair should be performed by only Lincoln Electric factory trained personnel.  
Unauthorized repairs performed on this equipment may result in danger to the technician or  
machine operator and will invalidate your factory warranty. For your safety and to avoid elec-  
trical shock, please observe all safety notes and precautions detailed throughout this manual.  
If for any reason you do not understand the test procedures or are unable to perform the  
test/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-  
ing assistance before you proceed. Call 1-800-833-9353 (WELD).  
DESCRIPTION  
This test will determine if the machine is capable of producing welding output as well as check  
and adjust, if necessary, the voltage and or current calibration.  
MATERIALS NEEDED  
Resistive Load Bank  
Calibrated Test Voltmeter  
Calibrated Test Ammeter  
POWER MIG 300  
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F-53  
F-53  
TROUBLESHOOTING & REPAIR  
VOLTAGE & CURRENT CALIBRATION PROCEDURE (continued)  
NOTE: Before attempting to calibrate the voltage  
CALIBRATION CHECK (CODE 10562)  
or current setting of the Power Mig, be  
The calibration of the Power Mig 300 can be  
sure to read the entire voltage or current  
checked using a resistive load bank with the  
calibration procedure. If the steps are not  
Power Mig 300 in mode 200. Mode 200 is a con-  
completed quickly, the machine will auto-  
stant current test mode.  
matically leave the calibration mode with-  
out changing the calibration settings. The  
voltage and current calibration settings of  
the Power Mig are completely indepen-  
dent of each other. Adjusting one will not  
affect the other.  
1. Toggle and hold the mode select switch in the  
up position.  
2. Turn on the Power Mig 300.  
3. Rotate the output knob, while still holding the  
mode select switch up, until the display reads  
“ALL nodE”.  
VOLTAGE CALIBRATION  
1. Connect the resistive load bank (approximate-  
ly .106 ohms or 250 amps) and test voltmeter  
to the welding output terminals.  
4. Release the mode select switch, toggle the  
mode switch one more time, then toggle the  
MODE SET switch until the MSPlll panel  
reads 200. Disengage the idler arm on the  
wire drive so no wire will feed.  
2. Toggle and hold in the mode select switch in  
the up position.  
3. Turn on the Power Mig 300.  
5. With the machine in mode 200 apply a resis-  
tive to the welding output terminals (approx.  
.106 ohms) set the machine output to 250  
amps and enable the weld terminals by  
pressing the trigger switch.  
4. Rotate the right hand output control knob until  
the display reads “vol cAL”.  
5. Release the mode select switch.  
6. Using the test meters note the output voltage  
and current.  
6. The left display will change to “VcAL” to indi-  
cate that voltage calibration is in progress.  
7. The Power Mig 300 voltmeter must match the  
test meter reading to within +/- 1 volt.  
7. The right hand display will scroll the following  
message: Adj rEnc SorEAL vol = 20V.  
8. The Power Mig 300 ammeter must match the  
test meter within +/- 5 amps.  
8. Adjust output control knob until the actual out-  
put voltage reading on the test volt meter is 20  
volts +/- .5 volts.  
9. If the volt meter does not meet the specifica-  
tion then proceed to the Voltage Calibration  
Procedure.  
10. If the ammeter does not meet the specifica-  
tion then proceed to the Current Calibration  
Procedure.  
POWER MIG 300  
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F-54  
F-54  
TROUBLESHOOTING & REPAIR  
VOLTAGE & CURRENT CALIBRATION PROCEDURE (continued)  
9. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
5. Release the mode select switch.  
6. The left display will change to “lcAL” to indi-  
cate that current calibration is in progress.  
10. Adjust the output control knob again if neces-  
sary to make the actual voltage output 20  
volts +/- .5 volts.  
7. The right hand display will scroll the following  
message: Adj rEnc SorEAL cur = 250A.  
11. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
8. Adjust the right hand output control knob until  
the actual output current reading on the test  
ammeter is 250 amps +/- 2A.  
12. Repeat the above two steps if necessary.  
13. Toggle the mode select switch up and release  
the switch to save the calibration setting.  
9. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
14. The right display will display the message  
“VcAL SAVEd”. Within 5 seconds, hold the  
mode set switch in the up position until the  
right display stops blinking.  
10. Adjust the output control knob again if neces-  
sary to make the actual output current read-  
ing on the test ammeter 250 amps +/- 2A.  
11. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
15. The machine will reset to normal operation  
after a few seconds.  
12. Repeat the above two steps if necessary.  
NOTE: If the mode select switch is not toggled  
within 30 seconds after adjusting the out-  
put control knob, the machine will leave  
the calibration mode and use the previ-  
ous calibration settings.  
13. Toggle the mode select switch up and release  
the switch to save the calibration setting.  
14. The right display will display the message  
“lcAL SAVEd”. Within 5 seconds, hold the  
mode set switch in the up position until the  
right display stops blinking.  
CURRENT CALIBRATION  
PROCEDURE  
1. Connect the resistive load bank of approx.  
.106 ohms and test ammeter to the welding  
output terminals.  
15. The machine will reset to normal operation  
after a few seconds.  
2. Toggle and hold the mode select button in the  
up position.  
NOTE: If the mode select switch is not toggled  
within 30 seconds after adjusting the out-  
put control knob, the machine will leave  
the calibration mode and use the previ-  
ous calibration settings.  
3. Turn on the Power Mig 300.  
4. Rotate the output control knob until the dis-  
play reads “cur cAL”.  
POWER MIG 300  
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F-55  
F-55  
TROUBLESHOOTING & REPAIR  
VOLTAGE & CURRENT CALIBRATION PROCEDURE (continued)  
NOTE: Before attempting to calibrate the voltage  
CALIBRATION CHECK  
(CODES 10952 AND UP)  
or current setting of the Power Mig, be  
sure to read the entire voltage or current  
The calibration of the Power Mig 300 can be  
checked using a resistive load bank with the  
Power Mig 300 in mode 200. Mode 200 is a con-  
stant current test mode.  
calibration procedure. If the steps are not  
completed quickly, the machine will auto-  
matically leave the calibration mode with-  
out changing the calibration settings. The  
voltage and current calibration settings of  
the Power Mig are completely indepen-  
dent of each other. Adjusting one will not  
affect the other.  
1. Toggle and hold the mode select switch in the  
up position.  
2. Turn on the Power Mig 300.  
VOLTAGE CALIBRATION  
1. Connect the resistive load bank (approximate-  
ly .106 ohms) and test voltmeter to the weld-  
ing output terminals.  
3. Once the display reads “Pres Spin” release  
the mode select switch. Rotate the output  
knob until the display reads “ALL nodE”.  
2. Toggle and hold in the mode select switch in  
the up position.  
4. Toggle the Mode Select switch once and wait  
for the machine to reset, then toggle the  
MODE SET switch until the MSPlll panel  
reads 200. Disengage the idler arm on the  
wire drive so no wire will feed.  
3. Turn on the Power Mig 300.  
4. Once the display reads “Pres Spin” release  
the mode select switch. Rotate the output  
knob until the display reads “vol cAL”.  
5. With the machine in mode 200 apply a resis-  
tive to the welding output terminals (approx.  
.106 ohms) set the machine output to 250  
amps and enable the weld terminals by  
pressing the trigger switch.  
5. Release the mode select switch once.  
6. Using the test meters note the output voltage  
and current.  
6. The left display will change to “VcAL” to indi-  
cate that voltage calibration is in progress.  
7. The Power Mig 300 voltmeter must match the  
test meter reading to within +/- 1 volt.  
7. The right hand display will scroll the following  
message: Adj rEnc SorEAL vol = 20V.  
8. The Power Mig 300 ammeter must match the  
test meter within +/- 5 amps.  
8. Adjust output control knob until the actual out-  
put voltage reading on the test volt meter is 20  
volts +/- .5 volts.  
9. If the volt meter does not meet the specifica-  
tion then proceed to the Voltage Calibration  
Procedure.  
10. If the ammeter does not meet the specifica-  
tion then proceed to the Current Calibration  
Procedure.  
POWER MIG 300  
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F-56  
F-56  
TROUBLESHOOTING & REPAIR  
VOLTAGE & CURRENT CALIBRATION PROCEDURE (continued)  
9. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
5. Toggle the Mode Select switch once.  
6. The left display will change to “lcAL” to indi-  
cate that current calibration is in progress.  
10. Adjust the output control knob again if neces-  
sary to make the actual voltage output 20  
volts +/- .5 volts.  
7. The right hand display will scroll the following  
message: Adj rEnc SorEAL cur = 250A.  
11. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
8. Adjust the right hand output control knob until  
the actual output current reading on the test  
ammeter is 250 amps +/- 2A.  
12. Repeat the above two steps if necessary.  
13. Toggle the mode select switch up and release  
the switch to save the calibration setting.  
9. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
14. The right display will display the message  
“VcAL SAVEd”. Within 5 seconds, hold the  
mode set switch in the up position until the  
right display stops blinking.  
10. Adjust the output control knob again if neces-  
sary to make the actual output current read-  
ing on the test ammeter 250 amps +/- 2A.  
11. Wait for the machine’s output to be automati-  
cally turned off and then back on.  
15. The machine will reset to normal operation  
after a few seconds.  
12. Repeat the above two steps if necessary.  
NOTE: If the mode select switch is not toggled  
within 30 seconds after adjusting the out-  
put control knob, the machine will leave  
the calibration mode and use the previ-  
ous calibration settings.  
13. Toggle the mode select switch up and release  
the switch to save the calibration setting.  
14. The right display will display the message  
“lcAL SAVEd”. Within 5 seconds, hold the  
mode set switch in the up position until the  
right display stops blinking.  
CURRENT CALIBRATION  
PROCEDURE  
1. Connect the resistive load bank of approx.  
.106 ohms and test ammeter to the welding  
output terminals.  
15. The machine will reset to normal operation  
after a few seconds.  
2. Toggle and hold the mode select button in the  
up position.  
NOTE: If the mode select switch is not toggled  
within 30 seconds after adjusting the out-  
put control knob, the machine will leave  
the calibration mode and use the previ-  
ous calibration settings.  
3. Turn on the Power Mig 300.  
4. Once the display reads “Pres Spin” release  
the mode select switch. Rotate the output  
knob until the display reads “cur cAL”.  
POWER MIG 300  
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F-57  
F-57  
TROUBLESHOOTING & REPAIR  
RETEST AFTER REPAIR  
Retest a machine:  
• If it is rejected under test for any reason that requires you to remove any part which could affect the machine’s  
electrical characteristics.  
OR  
• If you repair or replace any electrical components.  
TEST MODE  
5
INPUT IDLE WATTS AND AMPS  
Input Volts/Hertz  
Maximum Idle Watts  
Maximum Idle Amps  
230/60  
400  
4.25  
OPEN CIRCUIT VOLTAGE  
45-49 VDC  
WIRE SPEED RANGE  
50 - 700 IPM (1.27 - 17.8 m/minute)  
OUTPUT  
AMPS  
VOLTS  
200A  
27-30  
POWER MIG 300  
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G-1  
G-1  
ELECTRICAL DIAGRAMS  
TABLE OF CONTENTS  
-ELECTRICAL DIAGRAMS SECTION-  
ELECTRICAL DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SECTION G  
WIRING DIAGRAM (CODE 10562 ONLY-G3852). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-2  
WIRING DIAGRAM (CODE 10952 ONLY-G4068). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-3  
WIRING DIAGRAM (CODE 10958 AND 11000 ONLY-G4305) . . . . . . . . . . . . . . . . . . . . . . . . . . . G-4  
WIRING DIAGRAM (CODE 11097 AND 11098 ONLY-G4511) . . . . . . . . . . . . . . . . . . . . . . . . . . . G-5  
ENTIRE MACHINE SCHEMATIC (CODE 10958 and 11000 ONLY-G4315). . . . . . . . . . . . . . . . . G-6  
ENTIRE MACHINE SCHEMATIC (CODE 11097 and 11098 ONLY-G4512) . . . . . . . . . . . . . . . . . G-7  
CONTROL PC BOARD SCHEMATIC #1 (CODE 10562 - 11098 - G3789-1D0/1) . . . . . . . . . . . . G-8  
CONTROL PC BOARD SCHEMATIC #2 (CODE 10562 - 11098 - G3789-1D0/2) . . . . . . . . . . . . G-9  
CONTROL PC BOARD SCHEMATIC #3 (CODE 10562 - 11098 - G3789-1D0/3) . . . . . . . . . . . . G-10  
CONTROL PC BOARD SCHEMATIC #4 (CODE 10562 - 11098 - G3789-1D0/4) . . . . . . . . . . . . G-11  
CONTROL PC BOARD ASSEMBLY (CODE 10562 - 11098 - L11088-1) . . . . . . . . . . . . . . . . . . . *  
POWER SUPPLY PC BOARD SCHEMATIC (CODE 10562 - 11098 - G3631) . . . . . . . . . . . . . . G-12  
POWER SUPPLY PC BOARD ASSEMBLY (CODE 10562 - 11098 - G3632-2). . . . . . . . . . . . . . *  
CHOPPER PC BOARD SCHEMATIC (CODE 10562 - 11098 - M20046-1L2) . . . . . . . . . . . . . . . G-13  
CHOPPER PC BOARD ASSEMBLY (CODE 10562 - 11098 - L11497-1). . . . . . . . . . . . . . . . . . . *  
MSP3 PC BOARD SCHEMATIC (CODE 10562 - 11098 - L11612) . . . . . . . . . . . . . . . . . . . . . . . G-14  
MSP3 PC BOARD ASSEMBLY(CODE 10562 - 11098 - M19790-1). . . . . . . . . . . . . . . . . . . . . . . G-15  
FEEDER PC BOARD SCHEMATIC (CODE 10562 - 11098 - G3883 - SHEET 1) . . . . . . . . . . . . G-16  
FEEDER PC BOARD SCHEMATIC (CODE 10562 - 11098 - G3883 - SHEET 2) . . . . . . . . . . . . G-17  
FEEDER PC BOARD ASSEMBLY (CODE 10562 - 11098 - G3884) . . . . . . . . . . . . . . . . . . . . . . *  
SPOOL GUN PC BOARD SCHEMATIC (CODE 10562 - 11098 - G3997 - SHEET 1). . . . . . . . . G-18  
SPOOL GUN PC BOARD SCHEMATIC (CODE 10562 - 11098 - G3997 - SHEET 2). . . . . . . . . G-19  
SPOOL GUN PC BOARD ASSEMBLY (CODE 10562 - 11098 - M20159-1) . . . . . . . . . . . . . . . . *  
ENCODER PC BOARD SCHEMATIC (CODE 10562 ONLY - L11558) . . . . . . . . . . . . . . . . . . . . G-20  
ENCODER PC BOARD ASSEMBLY (CODE 10562 ONLY - L11559-2) . . . . . . . . . . . . . . . . . . . . G-21  
DISPLAY PC BOARD SCHEMATIC (CODE 10562 - 11098 - L11108) . . . . . . . . . . . . . . . . . . . . . G-22  
DISPLAY PC BOARD ASSEMBLY (CODE 10562 - 11098 - L11757-1) . . . . . . . . . . . . . . . . . . . . G-23  
* NOTE: Many PC Board Assemblies are now totally encapsulated and are therefore considered to be unservice-  
able. The Assembly numbers are provided on this page but the actual drawings are no longer included.  
POWER MIG 300  
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G-2  
G-2  
ELECTRICAL DIAGRAMS  
WIRING DIAGRAM - POWER MIG 300 CODE 10562 ONLY  
S3RS232  
CONNECTOR  
1
DIGITAL POWE R SUPPLY BOARD  
DISPLAY  
BOARD  
ENCODER  
BOARD  
MS P III  
BOARD  
CONTROL  
BOARD  
3233 471  
253  
254  
2
3
+
472  
C6  
6800/75  
3234  
253  
251  
4
254  
5
472B  
L2  
L9  
471B  
6
FLEX CIRCUIT  
1
2
X5  
X6  
SHIELDED  
CABLE  
251  
7
CONTROL  
RECTIFIER  
-
20  
+
3
SPOOL GUN  
BOARD  
FEEDER  
BOARD  
431  
1104  
406 402  
471  
472  
412 408 410  
411 407  
403  
437 405  
401  
4
1103  
5
L6  
L7  
SHIELDED  
CABLE  
J3  
6
FAN  
MOTOR  
7
SHIELDED  
CABLE  
8
9
FAN  
RELAY  
+
-
FAN  
715  
716  
10  
~
P.C. BOARD CONNECTION DETAIL  
X5  
X6  
401  
402  
403  
1
2
437  
431  
3
4
405  
406  
407  
408  
5
H1  
J99  
B1  
B2  
503  
503A  
B2  
6
X3  
J4  
C1  
C2  
C3  
B4  
7
H5 H2 H3 H4  
H1  
8
L1  
CHOKE  
B1  
B5  
115V  
B5  
9
(SHOWN  
CONNECTED  
FOR 230V)  
+S TUD  
901B  
L1  
L2  
410  
411  
412  
10  
11  
12  
901  
X4  
X1  
H2  
C4  
B6  
B3  
TP4  
L1  
L2  
LINE  
SWITCH  
2520  
2530  
H5  
H3  
RECONNECT PANEL  
H4  
H1  
R2  
903B  
1
2
3
4
R1  
C5  
2400/100  
502  
503  
TP6  
W
B
H1  
H1  
C
O
N
T
J5  
LEM  
H4  
-STUD  
G
H4  
X2  
B6  
MS P III BOAR D  
TP5  
502  
503A  
1
2
SET  
SELECT  
SWITCH  
3417  
1
2
3
4
3411  
1
2
3
4
5
6
7
8
3
SWITCH  
3415  
604  
607  
903  
4
802 801  
804 806  
R
O
L
TO +  
STUD  
5
3411A  
3411  
3411A  
3416  
3414  
3415  
3416  
3417  
6
J341  
GND  
4A  
4
7
3414  
300A CHOPPER BOARD  
GEARBOX  
2
8
E
D
2A  
75  
75A  
76  
FOOT  
AMPTROL  
J6  
WIRE  
DR IVE  
MOTOR  
9
F
C
DISPLAY  
SHIELDED  
CABLE  
J37  
J36  
FLEX  
604  
611  
10  
11  
12  
13  
14  
15  
16  
A
B
AMPHENOL  
P.C. BOARD  
76A  
B
77  
1
2
77A  
(VIEWED  
FROM  
831:B 832:W  
O
A
R
L3  
DIODE  
BRIDGE  
ENCODER  
FLEX  
REAR)  
76A  
3
P.C. BOARD  
4A  
E
G
B
4
SPOOL GUN/  
PUSH-PULL  
AMPHENOL  
F
2A  
D
J361  
615  
75A  
3218  
3214  
5
C
A
833  
SHIELDEDCABLE  
J34  
GUN TRIGGER  
6
TACH  
D
77A  
7
1
2
3
4
L4  
L5  
1
2
GAS  
SOLENOID  
8
LOCATED ON  
CASE FRONT  
9
3
L8  
SPOOL GUN/  
PUSH-PULL  
SWITCH  
10  
4
834  
5
6
LEAD COLOR CODE:  
B=BLACK OR GRAY  
R=RED OR PINK  
W=WHITE  
7
FLEX  
75  
3214  
2
3218  
3234  
3233  
3244  
3243  
832:W 834 836  
831:B 833 835  
852  
8
841:R  
76  
4
77  
844:B  
855  
8512  
847:U  
851  
J7  
9
G=GREEN (W/YELLOW STRIPE)  
10  
11  
12  
13  
14  
15  
16  
1
6
4
1
5
1
3
1
2
4
1
5
8
4
6
3
10  
2
1
8
1
6
7
1
715  
716  
7
12  
9
16  
6
14  
CONNECTOR CAVITY NUMBER ING SEQUENCE  
(VIEWED FROMCOMPONENT SIDE OF BOARD)  
801  
802  
1
2
3
4
5
6
7
8
FEEDER BOARD  
SPI SPOOL GUN BOARD  
L2 THRU L9ARE RF CHOKES  
804  
806  
J8  
ALL CASE FRONT COMPONENTS SHOWN VIEWED FROM REAR.  
PANEL RECEPTACLE CAVITY NUMBERING SEQUENCE  
(VIEWED FROM LEAD SIDE OF RECEPTACLE)  
3244  
1101  
1102 3243  
1102 1104  
1101 1103  
901 903  
3
6
9
2
5
8
1
4
7
1 2 3  
4 5 6  
7 8 9  
SHIELDEDCABLE  
9 PIN  
J50  
9 PIN  
P50  
12 -21- 2001A  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.  
POWER MIG 300  
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G-3  
G-3  
ELECTRICAL DIAGRAMS  
WIRING DIAGRAM - POWER MIG 300 CODE 10952 ONLY  
S3RS232  
CONNECTOR  
1
DIGITAL POWE R SUPPLY BOARD  
DISPLAY  
BOARD  
MS P III  
BOARD  
CONTROL  
BOARD  
3233 471  
253  
254  
2
3
+
472  
C6  
6800/75  
3234  
253  
251  
4
254  
5
472B  
L2  
L9  
471B  
6
FLEX CIRCUIT  
1
2
X5  
X6  
SHIELDED  
CABLE  
251  
7
CONTROL  
RECTIFIER  
-
20  
+
3
SPOOL GUN  
BOARD  
FEEDER  
BOARD  
431  
1104  
406 402  
471  
472  
412 408 410  
411 407  
403  
437 405  
1103  
401  
4
5
L6  
L7  
SHIELDED  
CABLE  
J3  
6
FAN  
MOTOR  
7
SHIELDED  
CABLE  
8
9
FAN  
RELAY  
+
-
FAN  
715  
716  
10  
~
P.C. BOARD CONNECTION DETAIL  
X5  
X6  
401  
402  
403  
1
2
437  
431  
3
4
405  
406  
407  
408  
5
H1  
J99  
B1  
503  
503A  
B2  
6
X3  
J4  
C1  
C2  
C3  
B4  
300A CHOPPER BOARD  
7
H5 H2 H3 H4  
H1  
8
L1  
CHOKE  
B1  
115V  
B5  
B2  
9
(SHOWN  
CONNECTED  
FOR 230V)  
+S TUD  
901B  
L1  
L2  
410  
411  
412  
B5  
901  
10  
11  
12  
X4  
X1  
H2  
C4  
B6  
B3  
TP4  
L1  
L2  
LINE  
SWITCH  
2520  
H5  
H3  
RECONNECT PANEL  
H4  
H1  
R2  
903B  
1
2
3
4
R1  
C5  
2400/100  
502  
503  
TP6  
W
B
H1  
H1  
C
O
N
T
R
O
L
J5  
LEM  
2530  
H4  
-STUD  
G
H4  
X2  
B6  
MS P III BOAR D  
TP5  
502  
503A  
1
2
SET  
SELECT  
SWITCH  
3417  
1
2
3
4
3411  
1
2
3
4
5
6
7
8
3
SWITCH  
3415  
604  
607  
903  
4
802 801  
804 806  
TO +  
STUD  
5
3411A  
3411  
3411A  
3416  
3414  
3415  
3416  
3417  
6
J341  
GND  
4A  
4
7
3414  
GEARBOX  
2
8
E
D
2A  
75  
75A  
76  
DISPLAY  
P.C. BOARD  
FOOT  
AMPTROL  
AMPHENOL  
J6  
WIRE  
DR IVE  
MOTOR  
J37  
FLEX  
9
F
C
604  
611  
10  
11  
12  
13  
14  
15  
16  
A
B
76A  
B
GUN  
TRIGGER  
77  
77A  
(VIEWED  
FROM  
REAR)  
PANEL ENCODERS  
VOLTS/TRIM WFS/AMPS  
831:B 832:W  
O
A
R
2
3
L3  
DIODE  
BRIDGE  
1
2
3
4
76A  
3
2
1
3
2
1
4A  
E
G
B
4
SPOOL GUN/  
PUSH-PULL  
AMPHENOL  
D
F
2A  
615  
SPOOL GUN/  
PUSH-PULL  
SWITCH  
75A  
3218  
3214  
5
C
A
833  
SHIELDEDCABLE  
J34  
6
TACH  
D
77A  
7
L4  
L5  
1
2
GAS  
SOLENOID  
8
852  
855A  
9
3
8511 858  
857 8510  
859  
855  
8512  
851  
L8  
10  
4
834  
5
FLEX  
6
7
75  
3214  
2
3218  
3234  
3233  
3244  
3243  
832 834 836  
8
841:R  
76  
4
77  
831 833 835  
844:B  
847:U  
J7  
9
10  
11  
12  
13  
14  
15  
16  
LEAD COLOR CODE:  
B=BLACK OR GRAY  
R=REDOR PINK  
W=WHITE  
4
3
1
2
4
1
1
1
5
715  
716  
8
1
4
6
3
2
G=GREEN (W/YELLOW STRIPE)  
1
1
6
5
1
8
7
801  
802  
1
2
3
4
5
6
7
8
FEEDER BOARD  
SPI SPOOL GUN BOARD  
7
12  
6
10  
9
16  
6
14  
CONNECTOR CAVITY NUMBER ING SEQUENCE  
(VIEWED FROMCOMPONENT SIDE OF BOARD)  
804  
806  
J8  
L2 THRU L9ARE RF CHOKES  
ALL CASE FRONT COMPONENTS SHOWN VIEWED FROM REAR.  
3244  
1101  
1102 3243  
1102 1104  
1101 1103  
PANEL RECEPTACLE CAVITY NUMBERING SEQUENCE  
(VIEWED FROM LEAD SIDE OF RECEPTACLE)  
901 903  
3
6
9
2
5
8
1
4
7
1 2 3  
4 5 6  
7 8 9  
SHIELDEDCABLE  
9 PIN  
J50  
9 PIN  
P50  
A
G4068  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-4  
G-4  
ELECTRICAL DIAGRAMS  
WIRING DIAGRAM - POWER MIG 300 CODE 10958 AND 11000 ONLY  
S3RS232  
CONNECTOR  
1
DIGITAL POWE R SUPPLY BOARD  
DISPLAY  
BOARD  
MS P III  
BOARD  
CONTROL  
BOARD  
3233 471  
253  
254  
2
3
+
472  
C6  
6800/75  
3234  
253  
251  
4
254  
5
472B  
L2  
L9  
471B  
6
FLEX CIRCUIT  
1
2
X5  
X6  
SHIELDED  
CABLE  
251  
7
CONTROL  
RECTIFIER  
-
20  
+
3
SPOOL GUN  
BOARD  
FEEDER  
BOARD  
431  
1104  
406 402  
471  
472  
412 408 410  
411 407  
403  
437 405  
1103  
401  
4
5
L6  
L7  
SHIELDED  
CABLE  
J3  
6
FAN  
MOTOR  
7
SHIELDED  
CABLE  
8
9
FAN  
RELAY  
+
-
FAN  
715  
716  
10  
~
P.C. BOARD CONNECTION DETAIL  
X5  
X6  
401  
402  
403  
1
2
437  
431  
3
4
405  
406  
407  
408  
5
H1  
J99  
B1  
B2  
503  
503A  
B2  
6
X3  
J4  
C1  
C2  
C3  
B4  
300A CHOPPER BOARD  
7
H5 H2 H3 H4  
H1  
8
L1  
CHOKE  
B1  
115V  
B5  
9
(SHOWN  
CONNECTED  
FOR 230V)  
+S TUD  
901B  
L1  
L2  
410  
411  
412  
B5  
901  
10  
11  
12  
X4  
X1  
H2  
C4  
B6  
B3  
TP4  
L1  
L2  
LINE  
SWITCH  
2520  
H5  
H3  
RECONNECT PANEL  
H4  
H1  
R2  
903B  
1
2
3
4
R1  
C5  
2400/100  
502  
503  
TP6  
W
B
H1  
H1  
C
O
N
T
R
O
L
J5  
LEM  
2530  
H4  
-STUD  
G
H4  
X2  
B6  
MS P III BOAR D  
TP5  
502  
1
2
SET  
SELECT  
SWITCH  
3417  
1
2
3
4
3411  
1
2
3
4
5
6
7
8
503A  
3
SWITCH  
3415  
604  
607  
903  
4
802 801  
804 806  
TO +  
STUD  
5
3411A  
3411  
3411A  
3416  
3414  
3415  
3416  
3417  
6
J341  
GND  
4A  
4
7
3414  
DIODE  
BRIDGE  
2
GEARBOX  
8
E
D
B
2A  
75  
75A  
76  
DISPLAY  
P.C. BOARD  
FOOT  
AMPTROL  
AMPHENOL  
J6  
J37  
FLEX  
WIRE  
DR IVE  
MOTOR  
9
F
C
604  
611  
10  
11  
12  
13  
14  
15  
16  
TACH  
A
76A  
B
GUN  
TRIGGER  
77  
77A  
(VIEWED  
FROM  
REAR)  
PANEL ENCODERS  
VOLTS/TRIM WFS/AMPS  
W
B
O
A
R
2
3
L3  
1
2
3
4
76A  
L8  
3
2
1
3
2
1
4A  
E
G
B
4
SPOOL GUN/  
PUSH-PULL  
AMPHENOL  
D
F
2A  
615  
SPOOL GUN/  
PUSH-PULL  
SWITCH  
75A  
3218  
3214  
5
C
A
833  
SHIELDEDCABLE  
J34  
6
D
77A  
7
L4  
L5  
1
2
GAS  
8
SOLENOID  
B
W
852  
855A  
9
3
8511 858  
857 8510  
859  
855  
8512  
851  
10  
4
834  
5
FLEX  
6
7
75  
3214  
2
3218  
3234  
3244  
3243  
832 834 836  
8
841:R  
76  
4
77  
3233  
831 833 835  
844:B  
847:U  
J7  
9
10  
11  
12  
13  
14  
15  
16  
LEAD COLOR CODE:  
B=BLACK OR GRAY  
R=REDOR PINK  
W=WHITE  
4
3
1
2
4
1
1
1
5
715  
716  
8
1
4
6
3
2
G=GREEN (W/YELLOW STRIPE)  
1
1
6
5
1
8
7
801  
802  
1
2
3
4
5
6
7
8
FEEDER BOARD  
SPI SPOOL GUN BOARD  
7
12  
6
10  
9
16  
6
14  
CONNECTOR CAVITY NUMBER ING SEQUENCE  
(VIEWED FROMCOMPONENT SIDE OF BOARD)  
804  
806  
J8  
L2 THRU L9ARE RF CHOKES  
ALL CASE FRONT COMPONENTS SHOWN VIEWED FROM REAR.  
3244  
1101  
1102 3243  
1102 1104  
1101 1103  
PANEL RECEPTACLE CAVITY NUMBERING SEQUENCE  
(VIEWED FROM LEAD SIDE OF RECEPTACLE)  
901 903  
3
6
9
2
5
8
1
4
7
1 2 3  
4 5 6  
7 8 9  
SHIELDEDCABLE  
9 PIN  
J50  
9 PIN  
P50  
B
G4305  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-5  
G-5  
ELECTRICAL DIAGRAMS  
WIRING DIAGRAM - POWER MIG 300 CODE 11097 AND 11098 ONLY  
S3 RS232  
CONNECTOR  
1
DIGITAL POWER SUPPLY BOARD  
DISPLAY  
BOARD  
MSP III  
BOARD  
CONTROL  
BOARD  
3233 471  
253  
254  
2
3
+
472  
C6  
6800/75  
3234  
253  
251  
4
254  
5
472B  
L2  
L9  
471B  
6
FLEX CIRCUIT  
1
2
X5  
X6  
SHIELDED  
CABLE  
251  
7
CONTROL  
RECTIFIER  
-
20  
+
3
1104  
406 402  
471  
472  
412 408 410  
411 407  
403  
405  
1103  
401  
4
P.C. BOARD CONNECTION DETAIL  
5
L6  
L7  
SHIELDED  
CABLE  
J3  
6
FAN  
MOTOR  
7
8
9
FAN  
RE LAY  
+
-
FAN  
715  
716  
10  
~
X5  
X6  
401  
402  
403  
1
2
3
4
405  
406  
407  
408  
5
H1  
H2  
503  
6
X3  
J4  
C1  
C2  
C3  
B4  
300A CHOPPER BOARD  
7
H5 H2 H3 H4  
H1  
B1  
B2  
503A  
B2  
8
L1  
CHOKE  
B1  
115V  
B5  
9
(SHOWN  
CONNECTED  
FOR 230V)  
+STUD  
901B  
L1  
L2  
410  
411  
412  
B5  
901  
10  
11  
12  
X4  
X1  
C4  
B6  
B3  
TP4  
L1  
L2  
LINE  
SWITCH  
2520  
H5  
H3  
RECONNECT PANEL  
H4  
H1  
R2  
903B  
1
2
3
4
LEM  
R1  
C5  
2400/100  
502  
503  
TP6  
W
B
H1  
H1  
C
O
N
T
R
O
L
J5  
B6  
2530  
H4  
G
H4  
X2  
MSP III BOARD  
1
4
2
3
-STUD  
GND  
TP5  
502  
503A  
TO + STUD  
GEARBOX  
4A  
4
1
2
2
SE T  
SE LECT  
802 801  
804 806  
3411  
1
2
3
4
E
D
B
2A  
75  
75A  
76  
3
SWITCH  
3415  
SWITCH  
3417  
F
C
FOOT  
AMPTROL  
AMPHENOL  
833  
604  
607  
903  
4
A
76A  
5
3411A  
3411  
3411A  
3416  
77  
DIODE  
BRIDGE  
3414  
3415  
3416  
3417  
DUAL PROCEDURE  
77A  
TRIGGER  
GAS  
SOLENOID  
6
J341  
5
(VIEWEDFROMREAR)  
TACH  
7
3414  
6
7
8
WIRE DRIVE  
MOTOR  
76A  
8
4A  
DISPLAY  
P.C. BOARD  
J6  
834  
E
G
B
J37  
FLEX  
9
SPOOL GUN  
PUSH-PULL  
AMPHENOL  
F
D
C
2A  
L8  
1
2
3
4
75A  
604  
611  
10  
11  
12  
13  
14  
15  
16  
A
3218  
3214  
836  
B
W
B
853  
8111  
PANEL ENCODERS  
VOLTS/TRIM WFS/AMPS  
L5  
77A  
851A  
O
A
R
2
3
4
5
2B  
L4  
L3  
2
3
2
1
3
2
1
615  
SPOOL GUN/  
PUSH-PULL  
SWITCH  
SHIELDED CABLE  
J34  
6
D
7
8
1
2
B
W
852  
851  
855A  
9
SPI SPOOL  
GUN BOARD  
3
8511 858  
857 8510  
859  
8512  
1
2
3
4
5
6
7
8
855  
77  
10  
4
3218  
3214  
5
6
FLEX  
8514  
76  
846  
J810  
7
832 834 836  
846  
1102  
8
3233  
1101  
846A  
841:R  
831 833 835  
844:B  
4
853  
847:U  
J7  
8514  
3234  
9
10  
11  
12  
13  
14  
15  
16  
75  
1
2
8111  
8115  
LEADCOLOR CODE:  
B=BLACK OR GRAY  
R=RED OR PINK  
4
2
4
1
3
1
1
1
1
10  
9
10  
9
2
3
4
5
6
7
8
9
W=WHITE  
8
1
5
7
715  
716  
4
6
3
2
8
G=GREEN (W/YELLOWSTRIPE)  
8
1
1
8
1
6
5
7
7
6
6
801  
802  
1
2
3
4
5
6
7
8
7
J86  
12  
6
10  
9
16  
6
14  
5
5
CONNECTOR CAVITY NUMBER ING SEQUENCE  
(VIEWED FROMCOMPONENTSIDE OF BOARD)  
4
4
FEEDER BOARD  
3
3
804  
806  
L2 THRU L9ARE RF CHOKES  
ALL CASE FRONT COMPONENTS SHOWN VIEWED FROM REAR.  
2
J8  
2
10  
1
1
8115  
PANEL RECEPTACLE CAVITY NUMBERING SEQUENCE  
(VIEWED FROM LEAD SIDE OF RECEPTACLE)  
1102 1104  
1101 1103  
901 903  
3
6
9
2
5
8
1
4
7
1 2 3  
4 5 6  
7 8 9  
9 PIN  
J50  
9 PIN  
P50  
A
G4511  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-6  
G-6  
ELECTRICAL DIAGRAMS  
SCHEMATIC - COMPLETE MACHINE - CODE 10958 AND 11000 ONLY  
5 3 1 G 4  
CHANGE DETAIL: VARIOUS CORRECTIONS.  
ENGINEERING CONTROLLED  
MANUFACTURER: No  
ALL LED's  
LIGHT  
GENERAL INFORMATION  
ELECTRICAL SYMBOLS PER E1537  
COLOR CODE  
CAVITY NUMBERING SEQUENCE  
(COMPONENT SIDE OF P.C. BOARD)  
BRIEFLY  
A DASH "-" SCROLLS  
ALONG DISPLAY BOARD  
(TAKES ABOUT 10 SECONDS)  
1
1
3
6
4
8
1
2
B -  
W -  
R -  
U -  
BLACK  
WHITE  
RED  
J83,J88  
J2,J84  
J81,J82  
5
4
3
4
BLUE  
1
8
LOCATED ON FRONT  
OF MACHINE'S BASE  
1
5
MACHINE DIS P LAYS  
SETTINGS OF LAST  
J1,J86  
J85,J87  
WE LD MODE OPE R ATION  
MAIN  
TRANSFORMER  
10  
16  
9
6
H1  
H2  
LOCATED ON  
MAC HI NE 'S B AS E  
(STORAGE  
H5 H2 H3 H4  
H1  
IF LAST MODE WAS CC  
AMP LED ILLUMINATES  
IF LAST MODE WAS CV  
WFS AND VOLTAGE  
IF LAST MODE WAS SYNERGIC  
WFS AND TR IM  
COMPARTMENT SIDE)  
LOCATED ON TOP OF  
MAIN T R ANS F OR ME R  
(SHOWN  
CONNECTED  
FOR 230V)  
L1  
L2  
OUTPUT  
RECTIFIER  
LED's ILLUMINATE WITH  
WITH COR R E S PONDING VALUE.  
RIGHT DISPLAY "OFF"  
LED's ILLUMINATE WITH  
LOCATED NEXT TO  
MAIN TR ANS FOR ME R  
(ON WIRE DRIVE SIDE)  
OUTPUT  
CHOKE  
CORRESPONDING VALUES.  
CORRESPONDING VALUES.  
L1  
L2  
LINE  
SWITCH  
H5  
H3  
RECONNECT PANEL  
H4  
2520  
H1  
H1  
CHOPPER P.C. BOARD  
(SCHEMATIC M19792-1)  
57 VAC  
80 VDC  
CURRENT  
TRANSDUCER  
R1  
W
B
2400/100  
-
H1  
2530  
H4  
E
C
G
H4  
115 VAC 30 VAC  
G
LOCATED ON  
CHOPPER BOARD  
ASSEMBLY  
X5 X6  
X3 X4  
121K  
LOCATED AT  
MAC HINE 'S BAS E  
(WIRE DRIVE SIDE)  
CONTROL RECTIFIER  
PWM=20KHZ 12V  
LOCATED ON  
TRANSFORMER  
BAFFLE  
-
FAN  
FAN STAYS ON FOR 5 MIN AFTER  
LAST GUN TRIGGER (WHEN 2/4  
IS CLOSED)  
FOR ALL FLEX AND  
SHIELDED CABLE  
CR1  
6 V  
+ 42VDC  
+
1
2
3
4
5
6
7
8
9
10  
+15V  
+5V  
DIGITAL POWER  
SUPPLY P.C. BOARD  
(SCHEMATIC G3631)  
FAN RELAY  
LOCATED ON  
TRANSFORMER  
BAFFLE  
6800/75  
/SS  
+15VDC CONTR OL BD SUPPLY  
-15VDC CONTROL BD SUPPLY  
+5VDC CONTR OL BD SUPPLY  
CONTROL BD SUPPLY COMMON  
CS1  
CS2  
CS3  
MISO  
SCK  
MOSI  
GRD  
2J41  
1J41  
1J42  
472  
471  
412  
411  
408  
410  
2J42  
3J42  
5J42  
TOROID  
LED2  
RED  
LED1  
RED  
TOROID  
CHOPPER  
SUPPLY  
ALL 3 LE D'S ILLUMINATE  
AT THERMAL TRIP.  
COMMON  
+20VDC  
1J43  
7J43  
ILLUMINATED LED  
431  
437  
SPI FLEX/SHIELDED  
CABLE SUPPLY  
INDICATES VOLTAGES ARE  
BEING SUPPLIED TO J42  
LOCATED ON  
SECONDARY  
WINDINGS  
LOCATED ON  
CHOPPER BOARD  
HEATS INK  
+5V  
+15V  
COMMON  
SPI DISPLAY  
L11757-1  
3J43  
6J43  
12J43  
SCHEMATIC: L11108  
YELLOW  
403  
402  
401  
ILLUMINATED LED  
INDICATES VOLTAGES ARE  
BEING SUPPLIED TO J43  
RS232 SUPPLY  
+5V  
COMMON  
4J43  
9J43  
406  
405  
503A  
CAN COMMUNICATION  
SUPPLY  
N.C.  
FOR WELD FILE  
DOWNLOADS  
LOCATED ON TOP  
OF P.C. BOARD  
COMPARTMENT  
N.C.  
+5V  
COMMON  
RED  
RED  
RED  
5J43  
10J43  
RED  
1104  
1103  
LOCATED AT BOTTOM OF  
P.C. BOARDCOMPARTMENT  
PLACED AT A 45ANGLE  
ILLUMINATES WHEN  
DISPLAYING WFS  
ILLUMINATES WHEN  
DISPLAYING AMPS  
ILLUMINATES WHEN  
DISPLAYING VOLTS  
ILLUMINATES WHEN  
DISPLAYING TR IM  
R232  
CONNECTOR  
LOCATED ON DIVIDER  
PANEL IN THE WIRE DRIVE  
COMPARTMENT  
+ 10VDC  
COM  
+ 10VDC  
CONTROL  
P.C. BOARD  
(SCHEMATIC G3789)  
CONTROLS THE  
FUNCTIONALITY OF  
THE MACHINE.  
3J2  
4J2  
1J2  
253  
254  
251  
TOROID  
DUAL E NCODE R PR E S E NT  
ON CODE 10562 ONLY  
LED1  
GREEN  
7 PIN  
SPOOL GUN/PUSH-PULL  
AMPTROL  
FEEDHEAD  
P.C. BOARD  
(SCHEMATIC G3883)  
TOROID  
MOTOR  
MOTOR  
+
-
FOR MECHANICAL ENCODERS,  
AVAILABLE ON CODE 10952 AND  
ABOVE , R E FER TO J85 ON FEEDHEAD  
P.C. BOARD. THE DISPLAY BOARD  
CONNECTS DIRECTLY TO THE MSP3  
OPTION PANEL.  
1
2
1J83  
2J83  
3J83  
4J83  
831  
832  
833  
834  
R13  
X2  
R10  
B
L11559-  
2
R5 R4 R9 R3 R8 R6 C5  
R
C6  
C7  
C2  
C8  
D1  
R12 R11  
LOCATED BEHIND THE  
INSULATING WIRE DRIVE  
PANEL. REMOVE THE  
WIR E DR IVE ASSEMBLY  
TO GAIN ACCESS.  
2
3
4
5
6
7
20  
A1  
A2  
GAS SOLENOID +  
GAS SOLENOID -  
PWM: PULSE WIDTH  
MODUL AT ION  
C4  
TP  
VOLTAGE BETWEEN  
801 AND 806 VARIES  
DEPENDING ON  
CURRENT THROUGH  
LEM 500A = -4V  
CONTROLS THE WIRE  
DRIVE FUNCTIONS AND  
THE GAS SOLENOID.  
B
A
+ 15VDC  
-15VDC  
+ 5VDC  
COM  
TP  
FLEX  
2
3
C9  
PWMCONTROLLED  
412  
411  
408  
410  
12J4  
11J4  
8J4  
X1  
6.5 VDC WHEN GAS  
FLOWING COIL  
ME AS UR E S 21 OHMS  
12 VDC COIL  
C3  
R1  
J36  
C1  
LOCATED ON  
CASE BACK  
J361  
SPOOL GUN/PUSH-PULL MOTOR  
0VDC @ 50 IN/MIN  
DUAL  
ENCODER  
10J4  
24VDC@ 700 IN/MIN  
SPOOL GUN  
P.C. BOARD  
(SCHEMATIC G3997-1)  
5K  
CONTROLS THE SPEED  
OF THE SPOOL /  
B
W
ACCESS THIS CONNECTOR  
BY REMOVING THE WIRE  
DR IVE ASSE MBLY  
TOROID  
+ 5VDC  
SPI SUPPLY +15VDC  
COM  
403  
402  
401  
3J4  
2J4  
1J4  
PUSH-PULL GUNS BY  
READING THE  
POTENTIOMETER.  
MOT OR / G E AR BOX  
TACH  
5VDC TACH SUPPLY  
TACH SIGNAL  
2.6 VDC @ 50 IN/MIN  
R
U
B
R
U
B
1
841  
847  
844  
1J84  
7J84  
4J84  
27.4 VDC @ 700 IN/MIN  
8 SECOND AVERAGE CURRENT  
LIMIT =3.5A  
RS232 SUPPLY +5VDC  
COM  
2
406  
405  
6J4  
5J4  
MS P 3 BOAR D  
(SCHEMATIC: L11612)  
TACH COM  
3
4
SHIELDED  
CABLE  
ME AS UR E B T O U  
JUMPER ARE SO THE  
CONTROL BOARD  
RECOGNIZES  
THAT IT IS IN A  
PM300  
ALLOWS THE SELECTION OF DIFFERENT WELD  
MODE S AND PR OCE S S E S .  
(LIMIT IS SOFTWARE SET)  
120 Hz @ 50 IN/MIN  
1.6 kHz@ 700 IN/MIN  
4J6  
10J6  
604  
LED2  
2A 76A  
4A 77A 75A  
LOCATED ABOVE WIRE  
DR IVE AS S E MBLY ON  
CENTER PANEL  
GUN TRIGGER SUPPLY  
GUN TRIGGER INPUT  
11J6  
12J6  
3214  
3218  
4J324  
8J321  
1J85  
2J85  
851  
852  
THIS LED WILL BE  
BLINKING IF THERE IS  
AN ER R OR  
+ 15VDC  
+5VDC  
+0VDC  
1J3  
2J3  
10J3  
611  
GREEN  
LED5  
CAN COMMUNICATION SUPPLY +5V  
0V  
TOROID  
4J11  
3J11  
1J11  
2J11  
1104  
1103  
1101  
1102  
LED3  
REMOTE  
+15VDC  
+5VDC  
COMMON  
GREEN  
CAN COMMUNICATION  
CAN COMMUNICATION  
B
C
A
76  
1J321  
2J321  
7J321  
1J32  
2J32  
1J86  
2J86  
10J86  
2J82  
1J82  
LED4  
REMOTE  
75  
GREEN  
LED6  
REMOTE  
77  
SHIELDED CABLE  
DIP SWITCHES  
DIP SWITCHES  
10J32  
LOCATED IN LEFT SIDE OF  
P.C. BOARDCOMPARTMENT  
GREEN  
SWITCHES MUST BE  
IN OFF POSITION  
SWITCHES MUST BE  
IN OFF POSITION  
TRIGGER  
COMMON  
+ 6VDC  
COM  
15J7  
16J7  
SELECT  
SWITCH  
SET  
SWITCH  
E
D
F
4
TRIGGER  
2
3J321  
6J321  
3J324  
4J324  
3243  
3243  
3244  
3J82  
4J82  
715  
716  
TO POWER FEEDHEAD BOARD +42VDC  
GREEN  
LED7  
3244  
GREEN LED's REMAIN  
SOLIDGREEN  
LOCATED TO THE RIGHT  
OF WIRE DRIVE ASSEMBLY  
ON CENTER PANEL  
REDLED's ARE SOLID AT  
POWER UP THEN BLANK  
LOCATED AT BOTTOM OF  
P.C. BOARDCOMPARTMENT  
6 PIN FOOT AMPTROL  
LOCATED ON DIVIDER  
PANEL IN THE WIRE DRIVE  
COMPARTMENT  
RED  
+15VDC  
855  
5J85  
12J85  
0V  
8512  
CONTROL P.C. BOARD LED LEGEND  
LED1: +15V POWER TO CONTROL P.C. BOARD  
LED2: -15V POWER TO CONTROL P.C. BOARD  
LED3: +5V FOR SPI CABLE  
LOCATED IN P.C. BOARD  
COMPARTMENT  
(LEFT FRONT SIDE)  
SPOOL GUN/  
PUSH-PULL  
SWITCH  
15VDC WHEN IN THE SPOOL GUN POSITION  
0VDC WHEN IN THE PUSH-PULL POSITION  
PANEL ENCODERS  
LOCATED ON  
CASEFRONT  
LED4: +15V FOR SPI CABLE  
WFS /AMPS  
VOLTS/TRIM  
LED5: +5V POWER TO CONTROL P.C. BOARD  
LED6: +5V FOR RS232 CONNECTOR  
LED7: A FATAL ERROR HAS OCCURED  
LED8: +5V FOR CAN COMMUNICATION  
LED9 AND LED10: ER R OR CODE . LED9 BLINKS ONCE  
THEN LED10 BLINKS ERROR CODE.  
COMPONENT VALUE UNITS:  
LEAD COLOR CODE:  
+
RECTIFIER BRIDGE  
USED ONLY FOR  
EXTERNAL DIODE  
(USED FOR MOTOR  
BRAKING)  
B-BLACK  
G-GREEN  
O-ORANGE  
R-RED  
U-BLUE  
W-WHITE  
Y-YELLOW  
CAPACITOR: MFD/VOLTS  
RESISTOR: OHMS/WATTS  
3
2
1
3
1
2
CONNECTOR PIN NUMBERS:  
EX. 12PIN CONNECTOR  
LOCATED IN P.C. BOARD  
COMPARTMENT  
FOR CODE 10952  
AND HIGHE R  
1
6
LABELS:  
COMMON  
7
12  
LATCH  
FRAME GROUND  
EARTH GROUND  
VIEW OF CONNECTOR ON PC BOARD  
THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OWNED BY LINCOLN GLOBAL, INC. AND MAY NOT BE DUPLICATED, COMMUNICATED  
TO OTHER PARTIES OR USED FOR ANY PURPOSE WITHOUT THE EXPRESS WRITTEN PERMISSION OF LINCOLN GLOBAL, INC.  
PROPRIETARY & CONFIDENTIAL:  
DESIGN INFORMATION  
REFERENCE:  
THE INFORMATION ON THIS  
PRINT IS FOR REFERENCE  
ONLY. COMPONENTS AND  
CIRCUITRY MAY BE DIFFE R E NT  
FROMANACTUAL MACHINE.  
EQUIPMENT TYPE:  
SUBJECT:  
PAGE _1__ OF ___  
DOCUMENT  
NUMBER :  
1
POWER MIG 300  
cstuble  
DRAWN BY:  
DOCUME NT  
MAC HINE S C HE MAT IC  
REVISION:  
ENGINEER: J. SKERBEC  
SCALE:  
MAT E R I AL  
NA  
APPR OVAL  
DATE:  
PROJECT  
G4315  
CRM22115-EE  
NUMBER :  
B
3-26-2003  
APPROVED:  
Approve  
NONE  
DISPOSITION:  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-7  
G-7  
ELECTRICAL DIAGRAMS  
SCHEMATIC - COMPLETE MACHINE - CODE 11097 AND 11098 ONLY  
2 5 1 G 4  
CHANGE DETAIL: RELEASED A.01 FROMX.  
ENGINEERING CONTROLLED  
MANUFACTURER: No  
ALL LED's  
LIGHT  
GENERAL INFORMATION  
ELECTRICAL SYMBOLS PER E1537  
COLOR CODE  
CAVITY NUMBERING SEQUENCE  
(COMPONENT SIDE OF P.C. BOARD)  
BRIEFLY  
A DASH "-" SCROLLS  
ALONG DISPLAY BOARD  
(TAKES ABOUT 10 SECONDS)  
1
1
3
6
4
8
1
2
B -  
W -  
R -  
U -  
BLACK  
WHITE  
RED  
J83,J88  
J2,J84  
J81,J82  
5
4
3
4
BLUE  
1
8
LOCATED ON FRONT  
OF MACHINE'S BASE  
1
5
MACHINE DIS P LAYS  
SETTINGS OF LAST  
J1,J86  
J85,J87  
WE LD MODE OPE R ATION  
MAIN  
TRANSFORMER  
10  
16  
9
6
H1  
H2  
LOCATED ON  
MAC HI NE 'S B AS E  
(STORAGE  
H5 H2 H3 H4  
H1  
IF LAST MODE WAS CC  
AMP LED ILLUMINATES  
IF LAST MODE WAS CV  
WFS AND VOLTAGE  
IF LAST MODE WAS SYNERGIC  
WFS AND TR IM  
COMPARTMENT SIDE)  
LOCATED ON TOP OF  
MAIN T R ANS F OR ME R  
(SHOWN  
CONNECTED  
FOR 230V)  
L1  
L2  
INPUT  
RECTIFIER  
LED's ILLUMINATE WITH  
WITH COR R E S PONDING VALUE.  
RIGHT DISPLAY "OFF"  
LED's ILLUMINATE WITH  
LOCATED NEXT TO  
MAIN TR ANS FOR ME R  
(ON WIRE DRIVE SIDE)  
OUTPUT  
CHOKE  
CORRESPONDING VALUES.  
CORRESPONDING VALUES.  
L1  
L2  
LINE  
SWITCH  
H5  
H3  
RECONNECT PANEL  
H4  
2520  
H1  
H1  
CHOPPER P.C. BOARD  
(SCHEMATIC M19792-1)  
57 VAC  
80 VDC  
CURRENT  
TRANSDUCER  
R1  
W
B
2400/100  
-
H1  
2530  
H4  
E
C
G
H4  
115 VAC 30 VAC  
G
LOCATED ON  
CHOPPER BOARD  
ASSEMBLY  
X5 X6  
X3 X4  
121K  
LOCATED AT  
MAC HINE 'S BAS E  
DIODE R ECTIFIER  
(WIRE DRIVE SIDE)  
PWM=20KHZ 12V  
LOCATED ON  
TRANSFORMER  
BAFFLE  
-
FAN  
LOCATED AT BOTTOM OF  
FAN STAYS ON FOR 5 MIN AFTER  
LAST GUN TRIGGER (WHEN 2/4  
IS CLOSED)  
P.C. BOARDCOMPARTMENT  
FOR ALL FLEX AND  
SHIELDED CABLE  
CR1  
15 V  
+ 42VDC  
+
DIGITAL POWER  
SUPPLY P.C. BOARD  
(SCHEMATIC G3631)  
1
2
3
4
5
6
7
8
9
10  
+15V  
+5V  
FAN RELAY  
LOCATED ON  
TRANSFORMER  
BAFFLE  
6800/75  
/SS  
+15VDC CONTR OL BD SUPPLY  
-15VDC CONTROL BD SUPPLY  
+5VDC CONTR OL BD SUP PLY  
CONTROL BD SUPPLY COMMON  
CS1  
CS2  
CS3  
MISO  
SCK  
MOSI  
GRD  
2J41  
1J41  
1J42  
472  
471  
412  
411  
408  
410  
2J42  
3J42  
5J42  
TOROID  
LED2  
RED  
LED1  
RED  
TOROID  
CHOPPER  
ILLUMINATED LED  
ALL 3 LE D'S ILLUMINATE  
AT THERMAL TRIP.  
SUPPLY  
INDICATES VOLTAGES ARE  
BEING SUPPLIED TO J42  
COMMON  
1J43  
7J43  
431  
437  
+20VDC  
SPI FLEX/SHIELDED  
CABLE SUPPLY  
LOCATED ON  
SECONDARY  
WINDINGS  
LOCATED ON  
CHOPPER BOARD  
HEATS INK  
+5V  
+15V  
COMMON  
ILLUMINATED LED  
INDICATES VOLTAGES ARE  
BEING SUPPLIED TO J43  
SPI DISPLAY  
L11757-1  
3J43  
6J43  
12J43  
SCHEMATIC: L11108  
YELLOW  
403  
402  
401  
RS232 SUPPLY  
+5V  
COMMON  
4J43  
9J43  
406  
405  
503A  
CAN COMMUNICATION  
SUPPLY  
N.C.  
FOR WELD FILE  
DOWNLOADS  
LOCATED ON TOP  
OF P.C. BOARD  
COMPARTMENT  
N.C.  
+5V  
COMMON  
RED  
RED  
RED  
5J43  
10J43  
RED  
1104  
1103  
1
2
ILLUMINATES WHEN  
DISPLAYING WFS  
ILLUMINATES WHEN  
DISPLAYING AMPS  
ILLUMINATES WHEN  
DISPLAYING VOLTS  
ILLUMINATES WHEN  
DISPLAYING TR IM  
R232  
CONNECTOR  
TOROID  
LOCATED ON  
CASE BACK  
LOCATED IN LEFT SIDE OF  
P.C. BOARDCOMPARTMENT  
+ 10VDC  
COM  
+ 10VDC  
PWMCONTROLLED  
6.5 VDC WHEN GAS  
FLOWING COIL  
ME AS UR E S 21 OHMS  
12 VDC COIL  
CONTROL  
P.C. BOARD  
(SCHEMATIC G3789)  
CONTROLS THE  
FUNCTIONALITY OF  
THE MACHINE.  
3J2  
4J2  
1J2  
253  
254  
251  
MOTOR  
MOTOR  
GAS SOLENOID +  
GAS SOLENOID -  
+
-
LED1  
GREEN  
1J83  
2J83  
3J83  
4J83  
831:B  
832:W  
833  
FEEDHEAD  
P.C. BOARD  
2
3
4
5
6
7
20  
834  
(SCHEMATIC G3883)  
PWM: PULSE WIDTH  
MODUL AT ION  
VOLTAGE BETWEEN  
801 AND 806 VARIES  
DEPENDING ON  
CURRENT THROUGH  
LEM 500A = -4V  
+ 15VDC  
-15VDC  
+ 5VDC  
COM  
412  
411  
408  
410  
12J4  
11J4  
8J4  
FLEX  
CONTROLS THE WIRE  
DR IVE FUNCTIONS AND  
THE GAS SOLENOID.  
B
W
ACCESS THIS CONNECTOR  
BY REMOVING THE WIRE  
DR IVE ASSE MBLY  
TOROID  
10J4  
MOTOR / G EAR BOX  
TACH  
5VDC TACH SUPPLY  
TACH SIGNAL  
TACH COM  
2.6 VDC @ 50 IN/MIN  
R
U
B
R
U
B
1
2
3
4
841  
847:U  
844:B  
1J84  
7J84  
4J84  
27.4 VDC @ 700 IN/MIN  
8 SECOND AVERAGE CUR R ENT  
LIMIT =3.5A  
ME AS UR E B TO U (120 Hz @ 50IN/MIN, 1.6 kHz@ 700 IN/MIN)  
+ 5VDC  
SPI SUPPLY +15VDC  
COM  
403  
402  
401  
3J4  
2J4  
1J4  
(LIMIT IS SOFTWARE SET)  
DUAL PR OCE DURE INPUT  
853  
3J85  
2J85  
4
2
LOCATED ABOVE WIRE  
DRIVE ASSEMBLY ON  
CENTER PANEL  
RS232 SUPPLY +5VDC  
COM  
DUAL PR OCE DURE SUPPLY  
2B  
406  
405  
6J4  
5J4  
MS P 3 BOAR D  
(SCHEMATIC: L11612)  
3
SHIELDED  
CABLE  
GUN TRIGGER INPUT  
852  
JUMPER ARE SO THE  
CONTROL BOARD  
RECOGNIZES  
THAT IT IS IN A  
PM300  
ALLOWS THE SELECTION OF DIFFERENT WELD  
MODE S AND PR OCE S S E S .  
GUN TRIGGER SUPPLY  
851A  
1
DIP S WITCHES  
851  
4
1J85  
4J85  
4J6  
10J6  
2
604  
LED2  
SWITCHES MUST BE  
IN OFF POSITION  
11J6  
12J6  
THIS LED WILL BE  
BLINKING IF THERE IS  
AN ER R OR  
+ 15VDC  
+5VDC  
+0VDC  
COMMON  
3233  
3J82  
4J82  
611  
1J3  
2J3  
GREEN  
TO POWER FEEDHEAD BOARD +42VDC  
LED5  
3234  
CAN COMMUNICATION SUPPLY +5V  
0V  
4J11  
3J11  
1J11  
2J11  
1104  
1103  
1101  
1102  
10J3  
LED3  
GREEN  
CAN COMMUNICATION  
CAN COMMUNICATION  
PANEL ENCODERS  
WFS /AMPS  
2J82  
1J82  
LED4  
+15VDC  
COMMON  
GREEN  
LED6  
VOLTS/TRIM  
5J85  
12J85  
855  
8512  
DIP SWITCHES  
7 PIN AMPTROL  
SPOOL/PUSH-PULL GUN  
GREEN  
LOCATED ON  
CASEFRONT  
RECTIFIER BRIDGE  
SWITCHES MUST BE  
IN OFF POSITION  
15VDC WHEN IN THE SPOOL GUN  
POSITION 0VDC WHE N IN THE  
PUSH-PULL POSITION  
+ 15VDC  
COM  
15J7  
16J7  
SELECT  
SWITCH  
SET  
SWITCH  
715  
716  
-
USED ONLY FOR  
GREEN  
LED7  
3
2
1
3
1
2
SPOOL GUN/PUSH-PULL MOTOR  
0VDC @ 50 IN/MIN  
SPOOL GUN/  
PUSH-PULL  
SWITCH  
835  
836  
5J83  
EXTERNAL DIODE  
(USED FOR MOTOR  
BRAKING)  
LOCATED ON  
DIVIDE R  
GREEN LED's REMAIN  
SOLIDGREEN  
LOCATED TO THE RIGHT OF WIRE  
DR IVE ASSEMBLY ON CENTER PANEL  
TOROID  
24VDC@ 700 IN/MIN  
REDLED's ARE SOLID AT  
POWER UP THEN BLANK  
PANEL IN THE  
WIR E DR IVE  
COMPARTMENT  
6J83  
5J88  
B
A
RED  
8J85  
11J85  
10J85  
9J85  
858  
8511  
8510  
859  
8115  
5K  
LOCATED IN P.C. BOARD  
COMPARTMENT  
LOCATED IN P.C. BOARD  
COMPARTMENT  
(LEFT FRONT SIDE)  
CONTROL P.C. BOARD LED LEGEND  
LED1: +15V POWER TO CONTROL P.C. BOARD  
LED2: -15V POWER TO CONTROL P.C. BOARD  
LED3: +5V FOR SPI CABLE  
LED4: +15V FOR SPI CABLE  
LED5: +5V POWER TO CONTROL P.C. BOARD  
LED6: +5V FOR RS232 CONNECTOR  
LED7: A FATAL ERROR HAS OCCURED  
LED8: +5V FOR CAN COMMUNICATION  
LED9 AND LED10: ERROR CODE. LED9 BLINKS ONCE  
THEN LED10 BLINKS ERROR CODE.  
7J85  
857  
E
F
C
D
G
8514  
846  
14J85  
6J84  
TO SPOOL/PUSH-PULL  
GUN MOTOR DRIVE  
SPOOL/PUSH-PULL GUN  
BRAKE SIGNAL  
(0 VOLT=MOTOR BRAKE)  
COMPONENT VALUE UNITS:  
LEAD COLOR CODE:  
0-5V SIGNAL VARIES WITH  
REMOTE POT WIPER  
846A  
8514  
3214  
3218  
6J810  
B-BLACK  
G-GREEN  
O-ORANGE  
R-RED  
U-BLUE  
W-WHITE  
Y-YELLOW  
CAPACITOR: MFD/VOLTS  
RESISTOR: OHMS/WATTS  
8115  
8111  
2J811  
1J811  
4J810  
3J810  
2J810  
+40VDC SUPPLY FOR  
4A  
76A  
77A 75A  
3214  
3218  
SPOOL/PUSH-PULL GUN MOTOR  
2A  
REMOTE  
76  
5J810  
8J810  
1J810  
CONNECTOR PIN NUMBERS:  
EX. 12PIN CONNECTOR  
76  
75  
77  
B
C
A
REMOTE  
75  
REMOTE  
77  
LOCATED ON  
DIVIDER  
TRIGGER  
D
E
2
TRIGGER  
4
1
6
PANEL IN THE  
WIR E DR IVE  
COMPARTMENT  
LABELS:  
PROVIDES BRAKING OF THE  
SPOOL/PUSH-PULL GUN  
MOTOR AND CONDITIONS  
THE SIGNAL FROM THE  
POTENTIOMETER.  
TOROID  
LOCATED INSIDE THE  
P.C. BOARD  
COMPARTMENT  
PLUGGED ONTO THE  
FEEDHEAD BOARD.  
F
COMMON  
SPOOL GUN  
P.C. BOARD  
7
12  
LATCH  
6 PIN FOOT AMPTROL  
FRAME GROUND  
EARTH GROUND  
(SCHEMATIC L12008-1)  
VIEW OF CONNECTOR ON PC BOARD  
THIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OWNED BY LINCOLN GLOBAL, INC. AND MAY NOT BE DUPLICATED, COMMUNICATED  
TO OTHER PARTIES OR USED FOR ANY PURPOSE WITHOUT THE EXPRESS WRITTEN PERMISSION OF LINCOLN GLOBAL, INC.  
PROPRIETARY & CONFIDENTIAL:  
DESIGN INFORMATION  
CDIEKMANN  
REFERENCE:  
THE INFORMATION ON THIS  
PRINT IS FOR REFERENCE  
ONLY. COMPONENTS AND  
CIRCUITRY MAY BE DIFFE R E NT  
FROMANACTUAL MACHINE.  
EQUIPMENT TYPE:  
SUBJECT:  
PAGE _1__ OF ___  
DOCUMENT  
NUMBER :  
1
POWER MIG 300  
DRAWN BY:  
DOCUME NT  
MAC HINE S C HE MAT IC  
REVISION:  
ENGINEER: JZUCKER  
SCALE:  
MAT E R I AL  
NA  
APPR OVAL  
DATE:  
PROJECT  
G4512  
CRM32923-B  
Name?:Creation Date  
NUMBER :  
A
APPROVED:  
-
NONE  
DISPOSITION:  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-8  
G-8  
ELECTRICAL DIAGRAMS  
SCHEMATIC - DIGITAL CONTROL PC BOARD #1 - CODE 10562 - 11098  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-9  
G-9  
ELECTRICAL DIAGRAMS  
SCHEMATIC - DIGITAL CONTROL PC BOARD #2 - CODE 10562 - 11098  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-10  
G-10  
ELECTRICAL DIAGRAMS  
SCHEMATIC - DIGITAL CONTROL PC BOARD #3 - CODE 10562 - 11098  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-11  
G-11  
ELECTRICAL DIAGRAMS  
SCHEMATIC - DIGITAL CONTROL PC BOARD #4 - CODE 10562 - 11098  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-12  
G-12  
ELECTRICAL DIAGRAMS  
SCHEMATIC - POWER SUPPLY PRINTED CIRCUIT BOARD - CODE 10562 - 11098  
+5V  
Machine Control Power Supply  
R50  
.13  
J42  
D18  
3
1
2
6A  
200V  
+
t
D4  
6A  
200V  
60V  
LED2  
10  
T1  
+5Volts, .750 Amp  
C43  
100  
16V  
C41  
100  
16V  
C39  
0.1  
50V  
T1  
C12  
33.2  
33.2  
10-55 VDC  
Operation  
.0015  
2000V  
332  
3
Vref  
1
10.0K  
10.0K  
10.0K  
R9  
11  
12  
D22  
10.0  
1.0A  
30V  
R60  
10.0  
D
S
+15Volts  
Q1  
21A  
200V  
G
R61  
10.0  
.750 Amp  
D24  
C13  
1
200V  
7
8
4
5
6
VCC  
OUT  
VFB  
1
5
Vref  
1
J41  
J41  
2
J42  
D3  
1A  
600V  
VREF  
RT/CT  
GND  
D19  
DZ8  
18V  
3W  
Vfb1  
OCI1  
2
4
X8  
1
DC Input (+)  
1
IN  
OUT  
COMP  
CS  
3A  
600V  
CNY17-3  
R10  
R5  
3
100K  
100K  
2
6
4
X5  
Vfb1  
ADJ  
9
+
t
7
D21  
1.0A  
30V  
C11  
22  
35V  
C14  
0.1  
50V  
C47  
1.0  
35V  
R55  
1.21K  
.33W  
R52  
221K  
T1  
1.82K  
T1  
OV1  
475  
Machine Control  
Shut Down  
4
6
C7  
0.1  
50V  
C45  
150p  
100V  
C6  
4.7  
35V  
R39  
R12  
5.62K  
Capacitor  
56.2K  
C8  
820p  
50V  
3W  
0.05  
C42  
R13  
C32  
2700p  
50V  
10p  
100V  
10.0K  
J41  
3
1
J41  
1
8
X1  
GND  
5
DC Input (-)  
REF  
TL431  
6
C44  
0.1  
50V  
C38  
4.7  
35V  
C40  
1.0  
35V  
-15Volts, .100Amp  
T1  
1.21K  
.33W  
5
J42  
J42  
8
ADJ  
J42  
2
IN  
OUT  
DZ1  
24V  
3W  
6
X9  
14  
D8  
1A  
600V  
gnd_mcps  
T2  
+5V  
Operation  
1
D25  
1.00K  
Undervoltage  
C31  
.0015  
2000V  
30-55 VDC  
Detect  
D2  
1A  
D23  
5
1
<30VDC  
600V  
1.0A  
30V  
OCI2  
CNY17-3  
D10  
X3  
D
Q2  
21A  
200V  
J42  
4
6
2
J43  
G
4
7
6
VCC  
OUT  
R32  
15.0  
6
S
IN  
OUT  
Vref  
2
8
4
5
2
VREF  
RT/CT  
GND  
VFB  
D9  
1A  
600V  
DZ2  
27V  
.5W  
C49  
.022  
R34  
221K  
DZ7  
18V  
3W  
1
COMP  
CS  
R31  
75K  
Vfb2  
ADJ  
3
3
C53  
.1  
R29  
X4  
C27  
C23  
1.0  
35V  
100K  
C25  
0.1  
50V  
OV2  
C24  
4.7  
35V  
C26  
1
200V  
1.21K  
.33W  
T2  
12  
150p  
100V  
D20  
1.0A  
30V  
C52  
150p  
DZ3  
27V  
.5W  
15Volts, .250Amps  
SPI  
gnd_mcps  
C2  
0.1  
50V  
C3  
4.7  
35V  
R38  
R28  
5.62K  
56.2K  
C4  
820p  
50V  
3W  
0.05  
Overvoltage  
Shutdown  
> 55 VDC  
C28  
10p  
100V  
249  
J43  
R40  
3
+
t
D16  
16A  
200V  
.13  
60V  
OV2  
OV1  
LED1  
2
+5Volts, 3 Amps  
SPI  
D14  
D17  
C37  
100  
16V  
C36  
100  
16V  
C35  
100  
16V  
C34  
0.1  
50V  
T2  
13  
150  
.33W  
150  
.33W  
150  
.33W  
D13  
Vref  
2
332  
DZ4  
3.3V  
3W  
C33  
4.7  
35V  
15  
J43  
D15  
X7  
5
IN  
OUT  
1A  
4
600V  
1
5
GND  
J43  
OCI3  
CNY17-3  
R17  
C5  
0.1  
50V  
C1  
4.7  
35V  
C30  
1.0  
35V  
+5Volts, .100 Amp  
CAN  
8
T2  
11  
150  
.33W  
+
t
D7  
1A  
2
6
4
.24  
Vfb2  
6
600V  
J43  
+20Volts  
.200 Amps  
Gate Drive  
475K  
R21  
10  
C21  
C17  
4.7  
35V  
C18  
4.7  
35V  
T2  
9
0.1  
2.49K  
.33W  
50V  
C46  
150p  
100V  
J43  
D12  
2
1.82K  
C16  
R22  
J43  
R24  
.24  
2700p  
50V  
10.0K  
7
J43  
D1  
+
t
D6  
1A  
X6  
4
1
IN  
OUT  
7
600V  
1A  
600V  
X2  
8
5
+20Volts  
.200 Amps  
Gate Drive  
GND  
REF  
TL431  
6
C22  
0.1  
50V  
C20  
4.7  
35V  
C19  
4.7  
35V  
T2  
8
C9  
0.1  
50V  
2.49K  
.33W  
C10  
4.7  
35V  
C29  
1.0  
35V  
+5Volts, .100 Amp  
RS232  
T2  
10  
150  
.33W  
J43  
11  
J43  
J43  
J43  
9
1
12  
FILENAME: G3631-2D2  
GENERAL INFORMATION  
ELECTRICAL SYMBOLS PER E1537  
LAST NO. USED  
R-  
C-  
D-  
CAPACITORS  
RESISTORS  
DIODES  
=
MFD  
(
.022/50V  
UNLESS OTHERWISE SPECIFIED)  
NOTES  
:
LABELS  
=
Ohms  
(
1/4W UNLESS OTHERWISE SPECIFIED)  
(UNLESS OTHERWISE SPECIFIED)  
N.A. SINCE COMPONENTS OR CIRCUITRY ON  
A
PRINTED CIRCUIT BOARD MAY CHANGE  
=
1A, 400V  
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY  
SUPPLY VOLTAGE NET  
POWER SUPPLY SOURCE POINT  
COMMON CONNECTION  
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING  
NUMBER.  
A
COMMON CODE  
FRAME CONNECTION  
EARTH GROUND CONNECTION  
THIS SHEET CONTAINS PROPRIETARY INFORMATION OWNED BY THE LINCOLN ELECTRIC COMPANY AND IS NOT TO BE REPRODUCED, DISCLOSED OR USED WITHOUT THE EXPRESS WRITTEN PERMISSION OF THE LINCOLN ELECTRIC COMPANY, CLEVELAND, OHIO U.S.A.  
UNLESS OTHERWISE SPECIFIED TOLERANCE  
"X" INFO.  
Chg. Sheet No.  
6-2-2000A  
DESIGN INFORMATION  
REFERENCE:  
MANUFACTURING TOLERANCE PER E2056  
EQUIPMENT TYPE:  
Di gi ta l S y s te ms  
Schematic, Digital Power Supply  
ON  
ON  
2
3
PLACE DECIMALS IS .02  
PLACE DECIMALS IS .002  
DRAWN BY: JP\TK  
ON ALL ANGLES IS .5 OF  
MATERIAL TOLERANCE ("  
A
DEGREE  
10-27-2000E  
SUBJECT:  
t
") TO AGREE  
ENGINEER:  
SUPERSEDING:  
WITH PUBLISHED STANDARDS.  
DATE:11- 30-98  
DRAWING No.:  
APPROVED:  
SCALE:NONE  
G 3631  
DO NOT SCALE THIS DRAWING  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-13  
G-13  
ELECTRICAL DIAGRAMS  
SCHEMATIC - CHOPPER BOARD - CODE 10562 - 11098  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-14  
G-14  
ELECTRICAL DIAGRAMS  
SCHEMATIC - MSP3 PC BOARD - CODE 10562 - 11098  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-15  
G-15  
ELECTRICAL DIAGRAMS  
PC BOARD ASSEMBLY - MSP3 PANEL - CODE 10562 - 11098  
ITEM  
REQ'D PART No.  
DESCRIPTION  
LED SPACER  
FLEX CIRCUIT  
1
2
3
8
1
T15176-2  
L11166-1  
.01 OZ. E3539  
ELECTRICAL INSULATING COMPOUND  
GROUND SIDE  
FOR ITEMS BELOW REFER TO ELECTRONIC COMPONENTS DATABASE FOR COMPONENT SPECIFICATIONS  
C1,C2,C3,C4,C5,C6,C7,C8,C10 15  
C11,C12,C13,C14,C15,C16  
S16668-11  
CAPACITOR,CEMO,0.1, 50V,10%  
C9  
1
1
1
1
8
S13490-104 CAPACITOR,TAEL,39,20V,10%  
2
DISP1  
S17395-9  
S18248-10  
S19365-8  
T13657-6  
LED,DISPLAY,7-SEGMENT,CC,4-DIGIT  
CONNECTOR,MOLEX,MINI,PCB,10-PIN  
CONNECTOR,PCB,MALE,RT-L,8-PIN  
LED,T-1,RED,HLMP-K101  
J34  
J341  
LED1,LED2,LED3,LED4,LED5  
LED6,LED7,LED8  
R1,R2,R12,R13,R14,R15,R16 16  
R17,R18,R19,R20,R21,R22  
R23,R24,R25  
S19400-1001 RESISTOR,MF,1/4W,1.00K,1%  
R3  
1
6
1
1
2
1
1
1
2
1
S19400-2670 RESISTOR,MF,1/4W,267,1%  
S19400-1212 RESISTOR,MF,1/4W,12.1K,1%  
S19400-2002 RESISTOR,MF,1/4W,20.0K,1%  
S19400-9091 RESISTOR,MF,1/4W,9.09K,1%  
R4  
R7  
M19790-2  
MSP OPTION  
PANEL  
C5  
R4,R5,R6,R7,R8,R9  
C4  
R8  
D
C1  
J34  
R10  
R11  
X1, X2  
X3  
R
X1  
X2  
C9  
X3  
S20496-1  
S17900-28  
S17900-8  
S17900-26  
S17900-10  
S19869-2  
IC,CMOS,DRIVER,DISPLAY,LED,CC,MCU  
R16  
R10  
R17  
R24  
S1  
LED  
DISP  
1
IC,CMOS,HEX,BUFFER,3-STATE,2-BIT,4-BI  
IC,CMOS,INVERTER,SCHMITT,HEX,HC14A(SS  
IC,CMOS,MUX,DAT,8-INPUT,HC151(SS)  
IC,CMOS,REGISTER,SHFT,S-PI/SO,8-BIT(S  
SWITCH,DIP,SPST,2-CIRCUITS  
2
1
O
N
X4  
C7  
J341  
X5  
C16  
C14  
C6  
C15  
X6, X7  
S1  
R19  
R18  
R15  
C11  
C2  
R21  
R20  
C12 C13  
C10  
R23  
UNLESS OTHERWISE SPECIFIED:  
CAPACITANCE = MFD/VOLTS  
INDUCTANCE = HENRIES  
RESISTANCE = OHMS  
A
1
M19790-2  
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is pro-  
vided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the  
machine.  
POWER MIG 300  
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G-16  
G-16  
ELECTRICAL DIAGRAMS  
SCHEMATIC - FEEDER PC BOARD BOARD - CODE 10562 - 11098 - SHEET 1  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-17  
G-17  
ELECTRICAL DIAGRAMS  
SCHEMATIC - FEEDER PC BOARD BOARD - CODE 10562 - 11098 - SHEET 2  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-18  
G-18  
ELECTRICAL DIAGRAMS  
SCHEMATIC - SPOOL GUN PC BOARD - CODE 10562 - 11098 - SHEET 1  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-19  
G-19  
ELECTRICAL DIAGRAMS  
SCHEMATIC - SPOOL GUN PC BOARD - CODE 10562 - 11098 - SHEET 2  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-20  
G-20  
ELECTRICAL DIAGRAMS  
SCHEMATIC - ENCODER PC BOARD - CODE 10562 ONLY  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-21  
G-21  
ELECTRICAL DIAGRAMS  
PC BOARD ASSEMBLY - ENCODER PC BOARD - CODE 10562 ONLY  
ITEM  
R
EQ'D PART No.  
L11166-1  
.01 OZ E3539  
S24951-4  
DESCRIPTION  
N.B.  
1
2
3
1
FLEX CIRCUIT  
N.B.  
ELECTRICAL INSULATING COMPOUND  
CPLD SOFTWARE  
1
FOR ITEMS BELOW, REFER TO ELECTRONIC COMPONENTS DATABASE FOR COMPONENT SPECIFICATION  
1.50  
A1,A2  
2
1
7
1
1
1
1
1
M17789-2  
ENCODER,ROTARY,OPTICAL,61JY2049  
CAPACITOR ,SMD,TANTALUM,47MF,20V,10%,S7343  
CAPACITOR ,SMD,CER AMIC,0.1MF,50V,10%,X7R ,S0805  
CAPACITOR ,PEMF,0.33,200V,10%  
B
R10  
R13  
L11559-  
C1  
S25024-7SMT  
S25020-3SMT  
S13490-94  
R
C6  
2
X2  
C2,C3,C4,C5,C6,C7,C8  
R5 R4 R9 R3 R8 R6 C5  
C7  
C2  
C8  
D1  
C9  
R12 R11  
A1  
A2  
D1  
S25040-5SMT  
S18248-10  
S24020-4  
DIODE,SMD,DUAL,0.200A,70V,UFR  
J36  
CONNECTOR,MOLEX,MINI,PCB,10-PIN  
CONNECTOR ,MOLEX,MINI,PCB,4-PIN,TIN  
C4  
TP  
J361  
R1  
S25001-2670SMT R ESISTOR ,SMD,267OHMS,1/4W,1206,1%,TR  
TP  
3
.75  
0
2
R3,R4,R5,R6,R8,R9  
10 S25000-1212SMT R ESISTOR ,SMD,METAL FILM,1/10W,12.1K,1%,S0805  
C9  
R10,R11,R12,R13  
X1  
R14  
R15  
R16  
1
1
1
1
1
S25000-1501SMT RESISTOR ,SMD,METAL FILM,1/10W,1.50K,1%,S0805  
S25000-28R 7SMT RESISTOR,SMD,METAL FILM,1/10W,28.7OHMS,1%,S0805  
S25000-4750SMT RESISTOR ,SMD,METAL FILM,1/10W,475OHMS,1%,S0805  
C3  
R1  
J36  
C1  
N.A. X1  
N.A. X2  
S25070-3SMT  
S17900-8SMT  
CPLD,PR OGR AMMABLE,XC9536,44-PIN,VQFP(SS)  
IC,SMD,CMOS,INVER TER ,SCHMITT,HEX,HC14A(SS)  
J361  
.15  
DUAL  
ENCODER  
0
4.85 5.00  
N.B.  
1
12-21-2001A  
11559-2  
L
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is pro-  
vided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the  
machine.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
G-22  
G-22  
ELECTRICAL DIAGRAMS  
SCHEMATIC - DISPLAY PC BOARD - CODE 10562 - 11098  
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.  
POWER MIG 300  
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G-23  
G-23  
ELECTRICAL DIAGRAMS  
PC BOARD ASSEMBLY - DISPLAY PC BOARD - CODE 10562 - 11098  
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is pro-  
vided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the  
machine.  
POWER MIG 300  
Download from Www.Somanuals.com. All Manuals Search And Download.  
SVM ERROR REPORTING FORM  
We need to know if there are errors in our manuals. We also value any suggestions as to  
additional tests or procedures that would make this SVM a better tool for you.  
If you discover new or different “Problems or Symptoms” that are not covered in the three col-  
umn troubleshooting chart, please share this information with us. Please include the  
machine’s code number and how the problem was resolved.  
Thank You,  
Technical Services Group  
Lincoln Electric Co.  
22801 ST. Clair Ave.  
Cleveland, Ohio 44117-1199  
FAX 216-481-2309  
SVM Number ___________________________  
Page Number if necessary__________________  
Your Company__________________________  
Your Name_____________________________  
Please give detailed description below:  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
SD287 01/99  
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Download from Www.Somanuals.com. All Manuals Search And Download.  

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