Lincoln Electric SVM 106-A service manual Auxiliary Circuits, Timer Kits

		THEORY OF OPERATION					E-5
TOCSectionto	TOCMasterto	FIGURE E.4 – AUXILIARY CIRCUITS.
Return	Return		OPTIONAL		GAS	OPTIONAL
						TIMER OR
			METER KIT		SOLENOID	BURNBACK KIT
				115 VAC

								SCR	CURRENT	5-95 VDC
										WIRE DRIVE
								POWER	LIMITING
										MOTOR
								CIRCUIT	CIRCUIT
TOC	TOC				8.8 VAC
			CIRCUIT	TRIGGER				115 VAC	CONTROL
			BREAKER	TRANS-
									BOARD
				FORMER
		FROM				DIODE
to Section	to Master				24 VAC
			115 VAC					CR1
		WELDING				RECTIFIER	24 VDC
										TO WELDING
		POWER				NETWORK		CONTROL
										CONTACTOR
		SUPPLY						RELAY
Return	Return									GUN
										TRIGGER
						WIRE		GROUND
						SPEED		LEAD
						CONTROL		PROTECTOR

TOC	TOC
Section	Master	AUXILIARY CIRCUITS	METER KITS
		TIMER KITS	The optional meter kit indicates the welding
to	to	The optional GMA Timer and Burnback kits	voltage from the electrode to the work. This
			voltage is measured from the contact block in
Return	Return
		these functions. Both kits provide a burnback
			While the analog meter kit does not require
		can be added to provide time delays for	the wire drive compartment to the work.
		control which maintains the welding power	any additional power, the digital meter kit is
		source contacts closed for a short time after
			powered by an 8.8 VAC signal from the
		the trigger is released. The timer kit also has
			trigger transformer. See Figure E.4.
		controls which can provide a gas preflow and
		postflow by controlling the timing of the gas
		solenoid. See Figure E.4.
to Section TOC	to Master TOC
Return	Return	NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
			LN-7 GMA WIRE FEEDER