Troubleshooting - Lincoln Electric COBRAMAX IM774 Operator's Manual

Section E

Troubleshooting

Trouble
No wire feed at gun,
feeder not operating, i.e., no
slave motor or brake solenoid.
No wire feed at gun, feeder
operating properly
Wire feeds, but welding wire is
not energized.
Wire feeds erratically.
Wire feeds one speed only.
Wire walks out of the drive
rolls.
Cause
115 VAC Control fuse in feeder/
Control box blown.
Micro-switch defective/not
being activated.
Broken electrical cable.
24 VAC Control fuse in feeder/
Control box blown.
Bad Potentiometer.
Broken Electrical Cable
Bad Speed control/PCB.
Loose or no cable connections.
Contactor control cable loose or
in wrong position
Welding power source.
Dirty or worn conduit.
Wrong size contact tip.
Idler roll stuck.
Bad potentiometer.
Broken electrical cable.
Bad speed control.
Idler roll upside-down.
Rear wire guide missing.
CobraMAX™ Owner's Manual - Page 7
Remedy
Replace fuse.
Replace switch. Check switch
for operation.
Check micro-switch wires for
continuity.
Check motor leads for shorts;
then replace fuse.
Check potentiometer with
meter.
Check motor and potentiometer
for continuity.
See specific cabinet/control
box owners manual for speed
control operation.
Check all power connections.
Check power supply owners
manual for location and type of
contactor signal required.
Check power source.
Blow out or replace conduit.
See contact tip table.
Check for lock washer under
idler roll, or replace if damaged.
Check with meter.
Check potentiometer wires for
continuity or short.
See specific cabinet/control
owners manual for speed
control operation.
Place groove in idler roll toward
top.
Replace wire guide.