Basic Welding Troubleshooting - Miller Auto-Continuum 350 Owner's Manual

6-8. Basic Welding Troubleshooting

Listed below are some problems, causes and remedies related to welding operations; however, this list does not contain every possible condition that
could be encountered in welding.
Trouble
No weld output; unit completely
inoperative.
Weld output is present, but wire stops
feeding while welding.
OM-273473 Page 34
Probable Cause
Line disconnect switch in Off position.
Power source switch in Off position.
Primary power fuse blown or circuit breaker
tripped.
Wire feeder protective fuse blown or circuit breaker
tripped.
Wire feeder drive rolls misaligned.
Wrong size drive rolls.
Too much or too little drive roll pressure.
Too much tension set at wire spool.
Restriction in unspooler or drum adapter.
Feeder motor burnt out.
Gun liner dirty or restricted.
Wrong type or size of liner.
Broken or damaged gun or torch.
Contact tip opening restricted.
Wrong size or type of contact tip.
Sharp bends or kinks in gun cable or liner.
Gun overheating.
Wrong size wire.
Guides rubbing on drive rolls.
Drive rolls jammed.
Motor cable disconnected or damaged.
Remedy
Place switch in On position.
Place switch in On position.
Replace fuse or reset circuit breaker and check in-
put voltage.
Replace fuse or reset circuit breaker and find over-
load condition.
Align drive rolls.
Replace with proper size drive rolls.
Adjust drive roll pressure.
Reduce wire spool tension.
Replace unspooler or repair restriction.
Test motor and replace if necessary.
Remove gun liner and clean or replace.
Install proper size liner.
Replace faulty parts.
Replace contact tip.
Replace with proper size and type contact tip.
Straighten gun cable and/or replace liner.
Use gun with proper amperage rating.
Match wire size to liner and contact tip.
Adjust or position guides properly.
Remove foreign object from gears.
Connect, repair or replace motor cable.