Miller Electric XMT 4-Rack manual Paralleling Welding Power Sources For Smaw, Cause fire

Set the Amperage/Voltage control on all paralleled welding power sources to the same value. The iso- lated terminal may be used as a common connection point if no other connections are made to it.

4-5. Paralleling Welding Power Sources For SMAW

WARNING

ELECTRIC SHOCK can kill.		ARCING can burn skin or damage
•	Do not touch live electrical parts.	electrical equipment.
•	Turn Off welding power sources by placing Power	•	Do not change position of the welding cable
	circuit breakers in the Off position before making any	•	connectors while welding.
•	weld output connections.		Be sure the connectors are secure in receptacles
	Do not connect welding output of different polarities		before welding.
•	to the same structure.	INADEQUATE		WORK	CABLE
	See ANSI Z49.1 and OSHA Title 29, Chapter XVII,
	Part 1910, Subpart Q (addresses at beginning of	CONNECTIONS		can cause	serious
•	manual).	damage to input power service and
	Do not handle or come in contact with two live	create a hazardous condition.
	electrodes at the same time.	•	Connect an electrical cable of adequate size
UNDERSIZED WELDING CABLES can			between the isolated terminal and the workpiece
			whenever any welding power sources are
cause fire.			connected to the isolated terminal.
•	Use single cables of adequate capacity to carry the

total combined amperage of the paralleled welding power sources.

		The procedure shown is for
		Electrode			Positive	welding
		connections.
		1	Weld Output Cables
		Determine cable sizes according to
		welding		power source		Owner’s
		Manual. Cables must reach cable
		connection			point. Cables con-
		nected together must be the same
		polarity.
		2	Connection Point
1		Cover		with	proper	insulating
		material after making connections.
		3	Terminal Lugs
		Use lugs of proper amperage
	1	capacity and hole size for connec-
		tion.
	4	4 Common Weld Output Cable
4		Cable must be able to carry com-
		bined weld output of all welding
	2	power sources connected in paral-
		lel. Use Table 4-1 to select proper
SMAW	–
	+	cable size.

1

Securely cover connection with proper insulating material.

3

For Electrode Negative, reverse cable connections. Positive (+)

weld output cables connect to work, negative (–) weld output cables go to electrode.

4

ST-158 334 / Ref. ST-154 540-A

Figure 4-5. Paralleling Welding Power Sources For SMAW

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