Miller Electric D-74S Welder User Manual


 
OM-1500-6 Page 22
7-3. Troubleshooting
Y Disconnect power before troubleshooting
Trouble Remedy
Wire feeds, shielding gas flows, but
electrode wire is not energized.
Check cable connections. Check cables for continuity, and repair or replace cables if necessary
(see Section 5-3).
Wire feeder is on, display does not light
up, motor does not run, gas valve and
welding power source contactor do not
pull in.
Check and reset circuit breaker at welding power source.
Electrode wire feeding stops or feeds
erratically during welding
Check gun trigger connection. See gun Owner’s Manual.
erratically during welding.
Check gun trigger. See gun Owner’s Manual.
Readjust hub tension and drive roll pressure (see Section 5-7).
Change to correct size drive roll (see 5-7).
Clean or replace dirty or worn drive roll.
Incorrect size or worn wire guides.
Replace contact tip or liner. See gun Owner’s Manual.
Remove weld spatter or foreign matter from around nozzle opening.
Have Factory Authorized Service Agency check drive motor or motor control board PC1.
Wire birdnests between feeder and
gun.
Gun liner has to large of diameter opening, is clogged, or the end of the gun is not close enough
to the front set of drive rolls.
Motor runs slowly. Check for correct input voltage.
Wire feeder power is on, displays light
up, but unit is inoperative.
Check welding gun trigger leads for continuity, and repair leads or replace gun.