Miller Electric 812, 652 manual Troubleshooting, Trouble Remedy

. A complete Parts List is available at www.MillerWelds.com

6-4. Troubleshooting

	Trouble		Remedy
No weld output; unit completely		Place line disconnect device in On position (see Section 4-18).
inoperative; pilot light PL1 off.
		Check for open line fuse(s), and replace if open (see Section 4-18).
		Check for proper input power connections (see Section 4-18).
		Check for proper jumper link position (see Section 4-17).
		Check fuse F1, and replace if necessary (see Section 6-2).
No weld output; power switch pilot light		Unit overheated. Allow unit to cool with fan On (see Section 4-2).
on.
		If using remote control, place Output (Contactor) switch in Remote 14 position, and connect remote
		control (see Sections 4-14and 4-15). If remote is not being used, place switch in On position (see
		Section 5-1).
		Check, repair, or replace remote control.
No weld output; power switch pilot light		Check for proper input power connections (see Section 4-18).
on; fan off.
		Check for open line fuse(s), and replace if open, or reset circuit breaker (see Section 4-18).
		Turn power switch off then back on. If no output condition remains, have Factory Authorized Service
		agent check SCR’s.
Limited weld output and low		Check position of Remote Amperage/Voltage Control switch (see Section 5-1).
open-circuit voltage.
		Check for open line fuse(s), and replace if open (see Section 4-18).
		Check for proper input power connections (see Section 4-18).
		Check for proper jumper link position (see Section 4-17).
		Clean and tighten all weld output connections.
Unit provides only maximum or		Have Factory Authorized Service Agent check control board PC1 and hall device HD1.
minimum weld output.
		Check position of Remote Amperage/Voltage Control switch (see Section 5-1).
Not able to obtain minimum output in		Use high inductance weld output terminal when in CC mode to obtain minimum output (see Section
CC mode.		4-9).
Erratic or improper weld output.		Use proper size and type of weld cable (see Section 4-9).
		Clean and tighten all weld connections.
		Check wire feeder installation according to Owner’s Manual.
		Check position of Process selector switch (see Section 5-1).
		Have Factory Authorized Service Agent check control board PC1 and hall device HD1.
No 115 volts ac output at duplex recep-		Reset supplementary protector CB1 (see Section 4-7).
tacle, or Remote 14 receptacle.
No 24 volts ac output at Remote 14 re-		Reset supplementary protector CB2 (see Section 4-7).
ceptacle.
Fan not operating. Note: fan only runs		Check for and remove anything blocking fan movement.
when cooling is necessary.
		Have Factory Authorized Service Agent check fan motor.
Wandering arc; poor control of arc		Reduce gas flow rate.
direction.
		Select proper size tungsten.
		Properly prepare tungsten.
Tungsten electrode oxidizing and not		Shield weld zone from drafts.
remaining bright after conclusion of
weld.
		Increase postflow time.
		Check and tighten all gas fittings.
		Properly prepare tungsten.
		Check for water in torch, and repair torch if necessary. See torch Owner’s Manual.
Digital meter not working properly.		Have Factory Authorized Service Agent check control board PC1 and connections, and replace if
		necessary.

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