Overload Protection; Troubleshooting - Miller Electric WC-115A Owner's Manual

5-1. Overload Protection

5-2. Troubleshooting

Trouble
Pressing gun trigger does not energize
weld control or welding wire.
For models without optional contactor
control: Pressing gun trigger feeds control: Pressing gun trigger feeds
wire but does not energize welding
wire.
For models with optional contactor
control: Pressing gun trigger feeds
wire but does not energize welding
wire.
Pressing gun trigger energizes wire,
but wire does not feed.
Erratic weld output.
Wire feeds erratically.
Wire feed speed does not switch from
run-in speed to weld wire feed speed.
Wire feeds, but burns back.
No gas flow.
Wire does not feed, and is not
energized on CC welding power
sources.
OM-1078 Page 18
2
1
Push And Turn Pull Out And
Replace F1
Secure plug PLG4 in 115 volts ac receptacle (see Sections 3-7 and 3-8).
Secure gun plug in Gun Control receptacle RC3 on weld control (see Section 3-4).
Check fuse F1 and replace if necessary (see Section 5-1).
See Troubleshooting Section of gun and/or welding power source Owner's Manual.
Secure plug PLG5 in 14 pin receptacle on welding power source (see Section 3-9).
See Troubleshooting Section of welding power source Owner's Manual.
See Troubleshooting Section of welding power source Owner's Manual. Check contactor visually for
closure.
See Troubleshooting Section of gun Owner's Manual.
Secure plug PLG4 in 115 volts ac receptacle (see Sections 3-7 and 3-8).
Secure gun plug in Gun Control receptacle RC3 on weld control (see Section 3-4).
Secure plug PLG5 in 14 pin receptacle on welding power source (see Section 3-9).
See Troubleshooting Section of gun and/or welding power source Owner's Manual.
See Troubleshooting Section of gun Owner's Manual.
Check reed relay, and replace if necessary. Check that weld cable is routed through reed relay.
Readjust ramp-up speed potentiometer R70 on motor control board PC1 (see Section 3-5).
Check gas hose and connections, and replace if necessary (see Section 3-4).
Connect voltage sensing lead to workpiece (see Section 3-5).
If fuse F1 opens, the weld control
shuts down. To check or change
F1, proceed as follows:
1 Fuse Holder Cover
2 Fuse (See Parts List For Fuse
Size)
Push And Turn
Remedy
Ref. 144 451-D / Ref. 800 185-A