Miller Electric WC-115A manual Overload Protection, Troubleshooting

5-1.	Overload Protection
			If fuse F1 opens, the weld control
			shuts down. To check or change
	1	2	F1, proceed as follows:
			1	Fuse Holder Cover
			2 Fuse (See Parts List For Fuse
				Size)
	Push And Turn	Pull Out And	Push And Turn
		Replace F1
				Ref. 144 451-D / Ref. 800 185-A
5-2.	Troubleshooting

Trouble	Remedy
Pressing gun trigger does not energize	Secure plug PLG4 in 115 volts ac receptacle (see Sections 3-7and 3-8).
weld control or welding wire.
	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.
For models without optional contactor	Secure plug PLG5 in 14 pin receptacle on welding power source (see Section 3-9).
control: Pressing gun trigger feeds
wire but does not energize welding	See Troubleshooting Section of welding power source Owner’s Manual.
wire.
For models with optional contactor	See Troubleshooting Section of welding power source Owner’s Manual. Check contactor visually for
control: Pressing gun trigger feeds	closure.
wire but does not energize welding
wire.
Pressing gun trigger energizes wire,	See Troubleshooting Section of gun Owner’s Manual.
but wire does not feed.
Erratic weld output.	Secure plug PLG4 in 115 volts ac receptacle (see Sections 3-7and 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.

Wire feeds erratically.	See Troubleshooting Section of gun Owner’s Manual.
Wire feed speed does not switch from	Check reed relay, and replace if necessary. Check that weld cable is routed through reed relay.
run-in speed to weld wire feed speed.
Wire feeds, but burns back.	Readjust ramp-up speed potentiometer R70 on motor control board PC1 (see Section 3-5).
No gas flow.	Check gas hose and connections, and replace if necessary (see Section 3-4).
Wire does not feed, and is not	Connect voltage sensing lead to workpiece (see Section 3-5).
energized on CC welding power
sources.

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