Troubleshooting - Miller Maxstar 300 DX Owner's Manual

5-4. Troubleshooting

Trouble
No weld output; unit completely
inoperative.
No weld output; meter display On.
Erratic or improper weld output.
No 115 volts ac output at duplex recep-
tacle.
Fan not operating.
Wandering arc
Tungsten electrode oxidizing and not re- Shield weld zone from drafts.
maining bright after conclusion of weld.
Place line disconnect switch in On position (see Section 3-14).
Check and replace line fuse(s), if necessary, or reset circuit breaker (see Section 3-14).
Check for proper input power connections (see Section 3-14).
If using remote control, be sure correct process is enabled to provide output control at Remote 14
receptacle (see Section 3-7 as applicable).
Input voltage outside acceptable range of variation (see Section 3-13).
Check, repair, or replace remote control.
Unit overheated. Allow unit to cool with fan On (see Section 3-3).
Use proper size and type of weld cable (see Section 3-6).
Clean and tighten all weld connections (see Section 3-6).
Reset circuit breaker CB1 (see Section 3-5).
Check for and remove anything blocking fan movement.
Have Factory Authorized Service Agent check fan motor.
Use proper size tungsten (see Section 8).
Use properly prepared tungsten (see Section 8).
Reduce gas flow rate (see Section 3-10).
Increase postflow time (see Section 4-11).
Check and tighten all gas fittings (see Section 3-10).
Water in torch. Refer to torch manual.
Remedy
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