Lincoln Electric AC-1200 manual Symptoms

E-2	TROUbLESHOOTING	E-2
	Observe all Safety Guidelines detailed throughout this manual

PRObLEMS

(SYMPTOMS)

POSSIbLE

CAUSE

RECOMMENDED

COURSE OF ACTION

Welder will not start.	Supply line fuse blown.	Look for possible cause and repair.
	Open supply line lead.	Replace fuse.
	Wrong supply line voltage.	Repair.
		Provide nameplate specified voltage.
Welder will not weld (Contactors	Electrode or ground cable loose or	Tighten connection or repair broken
operating properly)	broken.	cable.
	Welder control circuit dead: No volt-	Check Control Transformer primary
	age across Control Transformer X1-	voltage and if OK, replace trans-
	X2.	former.
Welder will not weld (Contactors not	Thermostat on coil tripped. Welder	Check operation of fans and make
operating).	overheated (Fan motors operating).	sure there is no obstruction to air
		flow. Do not operate in excess of
	Fuse (or thermostat – below code	welder rating.
	7600) on control panel open; Control
	circuit overloaded. (Fan motors oper-	SCR’s or diodes on heat sink
	ating)	assembly or P.C. board failed –see
		Trouble “Welder welds at max. or
	Circuit across #2 and #4 not working	min. only – no control”. Make repairs
	properly.	and replace fuse.
	Wire feeder control power; No volt-	Check connections at terminal strip
	age across #31 and #32.	and wire feeder. Relay contacts not
		closing. Repair as required.
		Check fuse and replace if no good.
Welder welds at min. only no control.	Remote control switch in wrong posi-	Switch to ‘Panel Control’ for welder
	tion.	rheostat. Control and “Remote
		Control” for other control.
	Control rheostat open.	Replace rheostat.
	Control circuit open.	1.No voltage across #41 and #44 –
		Repair broken leads or reconnect
	Open saturable reactor control coil	loose leads.
	or connection.	2. Diodes or SCR’s on heat sinks open
		or disconnected. Repair or replace.
		3. P.C. board plug disconnected – Check
		plug connection and plug in properly.
		4. P.C. board failed. Determine cause
		and replace board.
		5. Open circuit ar R1 – Repair or replace.
		Repair connection or replace coil.

CAUTION

If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.

IDEALARC® AC-1200