Troubleshooting - Miller Millermatic 355 Owner's Manual

7-5.

Troubleshooting

Trouble
No weld output; unit completely
inoperative.
No weld output; unit is on.
Erratic or improper welding arc or
output.
Fan not operating.
Weld settings turn RED, see section
6–2 for more details.
Place line disconnect switch in On position.
Check and replace line fuse(s), if necessary, or reset supplementary protector.
Be sure power cord is plugged in and that receptacle is receiving input power.
Check and secure loose weld cable(s) into receptacle(s).
Check and correct poor connection of work clamp to workpiece.
Use proper size and type of weld cable (see your Distributor).
Clean and tighten weld connections.
Verify electrode polarity; check and correct poor connections to workpiece.
Unit not warmed up enough to require fan cooling.
Check for and remove anything blocking fan movement.
Have Factory Authorized Service Agent check fan motor and control circuitry.
Machine is operating on single phase 208 VAC or 240 VAC. Machine is folding output back to 350
Amps.
Lower weld settings to reduce weld output.
Rewire and relink machine to either single phase 460/575 VAC or any three phase power.
Remedy
OM-288360 Page 61