Section 6 − Maintenance And Troubleshooting; Routine Maintenance; Unit Overload; Troubleshooting - Miller XPS 350 Owner's Manual

SECTION 6 − MAINTENANCE AND TROUBLESHOOTING

6-1. Routine Maintenance

3 Months
Replace unreadable labels.
Repair or replace cracked weld
cable.
Replace o-ring in electrode/gas
output receptacle if cracked.
6 Months
Blow out or vacuum inside.

6-2. Unit Overload

Thermal switches TP2 in SR1 and TP3−TP4 in XFMR protect the unit from damage due to overheating. If thermal indicator PL2 illuminates, wait for
unit to cool (see Section 3-4) allowing fan motor to run before trying to weld. If unit is cool and no weld output continues, contact a Factory Authorized
Service Agent.

6-3. Troubleshooting

Trouble
No weld output; unit completely inoper-
ative.
No weld output; pilot light PL2 on.
Limited weld output, and low open cir-
cuit voltage.
Unit provides only maximum or minim-
um weld output.
OM-249 332 Page 24
! Disconnect power before maintaining.
.
Maintain more often during severe conditions.
OR
Remedy
Place line disconnect switch in On position (see Section 4-11).
Check and replace line fuse(s), if necessary, or reset circuit breaker (see Section 4-11).
Check for proper input power connections (see Section 4-11).
Check for proper jumper links position (see Section 4-10).
Have factory Authorized Service Agent check continuity of power switch S1, and replace if necessary.
Unit overheated. Allow unit to cool (see Section 3-4).
Check for proper input power connections (see Section 4-11).
Check for proper jumper links position (see Section 4-10).
Clean and tighten all weld output connections.
Have factory Authorized Service Agent check control board PC1 and Hall device HD1, and replace if ne-
cessary
Clean and tighten weld terminals.
Repair or replace cracked gas
hose.