Miller Electric MARK VIII-2 Troubleshooting, Turn Off polyweld system, and disconnect input power

6-4. Troubleshooting

			Y Turn Off polyweld system, and disconnect input power
			before inspecting, maintaining, or servicing.
	Trouble		Remedy
No weld output from any module; fan		Place line disconnect device in On position (see Section 4-10).
motors off; pilot light off.
		Check line fuse(s), and replace if needed. Reset circuit breakers (see Section 4-10).
		Check for proper input connections (see Section 4-10).
		Check position of input voltage jumper links (see Section 4-10).
		Be sure power switch is On (see Section 5-3).
		Check fuse F3 and/or F4, and replace if needed (see Section 6-2).
		Have Factory Authorized Service Station/Service Distributor check Start/Stop push buttons PB1/PB2
		and replace if necessary.
No weld output from any module; fan		Thermostat TP1 open (overheating). Allows fans to run; thermostat closes when unit has cooled (see
motors on; pilot light off.		Section 6-2).
No weld output from any module; fan		Have Factory Authorized Service Station/Service Distributor check contactor W and replace if needed.
motors on; pilot light on.
Limited output and low open circuit volt-		Check incoming power for correct voltage. Replace line fuse if open or reset circuit breaker (see Section
age from All modules.		4-10).
		Check position of input voltage jumper links (see Section 4-10).
No weld output from one module only.		Check fuse links, and replace if needed (see Section 6-2).
Low weld output from one module only.		Place Remote Amperage control switch in Off position or connect remote amperage control to Remote
No amperage control.		Amperage Control receptacle (see Section 5-2).
		Check module fuse link, and replace if needed (see Section 6-2).
		Reset module supplementary protector (see Section 6-2).
		Module thermostat open (overheating). Allow module to cool down; thermostat closes when module has
		cooled (see Section 6-2).
Erratic weld output.		Tighten all weld cable connections (see Section 4-6).
		Check for proper size and type of cable (see Section 4-10).
		Check for proper input and output connections (see Sections 4-10and 4-6).
		Use dry, properly stored electrodes.
No weld output at 115 volts ac duplex		Reset overload supplementary protector CB1 (see Section 6-2).
receptacle.
		Check fuse F3 and/or F4, and replace if needed (see Section 6-2).
Fan motor(s) does not run when On		Check fuse F3 and/or F4, and replace if needed (see Section 6-2).
push button is pressed.
		Have Factory Authorized Service Station/Service Distributor check control relay CR1 and fan motor FM1
		or FM2.
For GTAW, wandering arc − poor control		Select proper size tungsten (see Section 8-1).
of direction of arc.
		Properly prepare tungsten (see Sections 8-2or 8-3).
Tungsten electrode oxidizing and not re-		Shield weld zone of drafts.
maining bright after conclusion of weld.
		Properly prepare tungsten (see Sections 8-2or 8-3).
		Replace torch parts if water has leaked into torch.

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