MK Products Cobra SX LE Com AC only - Manual (Page 14)

Cobra ® SX Lincoln Compatible ™ Owner's Manual - Page 6
Section E Troubleshooting
Trouble Cause Remedy
No wire feed at gun, feeder
not operating, I.e. no slave
motor or brake solenoid.
Input power fuse in feeder/
Control box blown. Replace fuse.
Micro-switch defective/not
being activated. Replace switch. Check switch for
operation.
Broken electrical cable. Check micro-switch wires for
continuity
No wire feed at gun, feeder
operating properly
Motor Control fuse in feeder/
Control box blown. Check motor leads for shorts; then
replace fuse.
Bad potentiometer. Check potentiometer with meter.
Broken electrical cable. Check motor and potentiometer
wires for continuity.
Bad speed control/PCB.
See specific cabinet/control box
owners for speed control operation.
Wire feeds, but welding wire
is not engergized.
Loose or no cable connections. Check all power connections.
Contactor control cable loose or
in wrong position. Check power supply owners
manual for location and type of
contactor signal required, i.e.,
closing or 115VAC.
Welding power source. Check power source.
Wire feeds erratically.
Dirty or worn conduit. Blow out or replace conduit.
Wrong size contact tip. See contact tip table.
Idler roll stuck. Check for lock washer under idler
roll, or replace if damaged.
Wire feeds one speed only.
Bad potentiometer. Check with meter.
Broken electrical cable. Check potentiometer wires for
continuity or short.
Bad speed control.
See specific cabinet/control box
owners for speed control operation.
Wire walks out of drive rolls.
Idler roll upside-down. Place groove in idler roll toward
top.
Rear wire guide missing. Replace wire guide.