Lincoln Electric DC-655 Welding Performance, LOW Inductance Terminal, CV Mode CURRENT-LIMITING

		B-8			OPERATION						B-8
TOC	TOC	WELDING PERFORMANCE				As a general guideline for CC welding, set Arc Force to
Section	Master					“Mid” position and increase (typically to no more than
		LOW INDUCTANCE TERMINAL				#7) as necessary to prevent “stubbing” or “pop-outs”
		The inside right Negative (-) terminal is lower choke				while welding. This higher arc force is recommended
to	to					especially for low end 6010 stick welding.
		inductance and presently is only recommended for
Return	Return					OCV
		welding		with NR203Ni 1% procedures.	All other
						VOLTS
		processes are to be welded using the outside right
		Negative (-) terminal with higher choke inductance.
		CV MODE CURRENT-LIMITING						Hot Start
		CV MIG and CV Sub-Arc modes employ electronic							Min. Arc Force	Max. Arc Force
		current limiting to limit excessive short circuit output
		current which can result in undesirable arc character-
		istics or nuisance over current protection shutdown
TOC	TOC	(see Machine Protection section).					Low
		As shipped, the DC-655 is set for “Hi” current limiting,							Hi		AMPS
							Setting
									Setting
		which maintains constant voltage until the welding
Section	Master								CC OUTPUT
		current exceeds a level proportional to the voltage set-
		ting, then falls off linearly at about 10 volts per 100
to	to	amps to a limited short circuit current. “Lo” current				CC MODE HOT START
		limiting provides the same short circuit current, but the
Return	Return					Hot start is built-in for CC mode stick and carbon arc
		arc voltage begins to linearly fall off at lower current, at
						starting. Hot		Start provides an		extra	weld current
		about 5 volts per 100 amps.
						“boost” at the arc strike which increases with higher
		“Hi” is recommended for all CV processes, especially
						current	settings.		This Hot Start	level	exponentially
		for CV subarc and CV arc gouging, but “Lo” tends to				decays to the weld current setting in a few seconds.
		“soften” the arc more when welding NR203Ni 1% on				Adjustment of the Hot Start shouldn’t be necessary,
		the	Low	Inductance (-) terminal. If “Lo”	is desired,
						but an unsealed trimmer (R81) is provided on the DC-
		switch #4(right-most) of the DIP switch located on the
						655 Control PC Board to adjust hot start. Full counter-
		lower-center of the DC-655 Control PC board needs to
						clockwise adjustment will reduce Hot Start to zero.
		be switched from up (Hi) position to down (Lo) posi-
TOC	TOC	tion.
								Switch #3 is for test
Section	Master		VOLTS
						DIP Switch		purposes. Keep down.
								(as shown)			CC Hot Start
		High				1	2	3	4		Trimmer
to	to	Setting		"HI" Current Limit
Return	Return			"Lo" Current Limit
		Low				Switch #4 "Hi"CV Current
		Setting				Limit (as shown)
							Note: See Machine Shutdown section
								for use of switch #1 and #2.
				CV OUTPUT	AMPS		DC-655 Control PC Board

		CC MODE ARC FORCE	CC MODE ARC GOUGING
TOC	TOC	Arc Force provides extra weld current which linearly	The DC-655 is rated for air carbon arc gouging with up
		increases as the welding voltage decreases below a
			to 3/8” (10mm) diameter carbons. CC mode gouging
Section	Master	level determined by the constant current setting. The	bing.
		cover, adjust Arc Force from “Min” (no current
		Arc Force control knob, located behind the latched	is often preferred over CV mode for cutting control, but
			some Arc Force may be required to avoid carbon stub-
Return to	Return to	increase) to “Max” (about 9A/V increase).
		IDEALARC DC-655