Miller Electric AA40GBU - Manual (Page 22)

OM-227 674 Page 18
4-3. Troubleshooting
Trouble Remedy
Electrode wire feeding stops or feeds er-
ratically during welding
Readjust hub tension and drive roll pressure.
ratically during welding.
Change to correct size drive roll.
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 gun nozzle opening.
Check and secure motor plug connection.
Have Factory Authorized Service Agent check drive motor.
Motor runs slowly. Reduce load.
Check for correct input voltage.
Motor runs at full speed regardless of
wire speed setting.
Have Factory Authorized Service Agent check digital wire drive motor Tachometer board and encoder.
SECTION 5 − ELECTRICAL DIAGRAM
221 660-A
Figure 5-1. Circuit Diagram For AA40GBU/Gas Box (Left Hand)