Lincoln Electric IM700-D manual Table B.3 Typical Current Ranges 1 for Tungsten ELECTRODES2

B-9				OPERATION						B-9
		Table B.3 TYPICAL CURRENT RANGES (1) FOR TUNGSTEN ELECTRODES(2)
			DCEN (-)	DCEP (+)	Approximate Argon Gas Flow Rate
						C.F.H. (l/min.)
	Tungsten
	Electrode								TIG TORCH
			1%, 2%	1%, 2%
	Diameter								Nozzle
			Thoriated	Thoriated	Aluminum		Stainless Steel
	in. (mm)								Size (4), (5)
			Tungsten	Tungsten
	0 .010	(.25)	2-15	(3)	3-8	(2-4)	3-8	(2-4)	#4, #5, #6
	0.020	(.50)	5-20	(3)	5-10	(3-5)	5-10	(3-5)
	0.040	(1.0)	15-80	(3)	5-10	(3-5)	5-10	(3-5)
	1/16	(1.6)	70-150	10-20	5-10	(3-5)	9-13	(4-6)	#5, #6
	3/32	(2.4)	150-250	15-30	13-17	(6-8)	11-15	(5-7)	#6, #7, #8
	1/8	(3.2)	250-400	25-40	15-23	(7-11)	11-15	(5-7)
	5/32	(4.0)	400-500	40-55	21-25	(10-12)	13-17	(6-8)	#8, #10
	3/16	(4.8)	500-750	55-80	23-27	(11-13)	18-22	(8-10)
	1/4	(6.4)	750-1000	80-125	28-32	(13-15)	23-27	(11-13)

(1)When used with argon gas. The current ranges shown must be reduced when using argon/helium or pure helium shielding gases.

(2)Tungsten electrodes are classified as follows by the American Welding Society (AWS):

Pure	EWP
1% Thoriated	EWTh-1
2% Thoriated	EWTh-2

Though not yet recognized by the AWS, Ceriated Tungsten is now widely accepted as a substitute for 2% Thoriated Tungsten in AC and DC applications.

(3)DCEP is not commonly used in these sizes.

(4)TIG torch nozzle “sizes” are in multiples of 1/16ths of an inch:

# 4 = 1/4 in.		(6 mm)
# 5	= 5/16 in.	(8 mm)
# 6	= 3/8 in.	(10 mm)
# 7	= 7/16 in.	(11 mm)
# 8	= 1/2 in.	(12.5 mm)
#10 = 5/8 in.		(16 mm)

(5)TIG torch nozzles are typically made from alumina ceramic. Special applications may require lava nozzles, which are less prone to breakage, but cannot withstand high temperatures and high duty cycles.

Commander 300 SETTINGS WHEN USING THE K799 HI-FREQ UNIT

•Set the WELD MODE switch to the “20-250 setting” (TIG)

•. Set the IDLER switch to the “HIGH “ position.

•Set the WELDING TERMINALS switch to the “Weld Terminals On” position. This will close the solid state contactor and provide an always “hot” electrode.

(Note: This is necessary because the K799 circuitry with respect to the #2 and #4 leads does not provide the prop- er signal to open and close the solid state contactor in the Commander 300).

Commander 300 SETTINGS WHEN USING THE K930-1 or -2 TIG MODULE

•Set the WELD MODE switch to the 20-250 Setting (TIG).

•Set the IDLER switch to the “AUTO “ position.

•Set the WELDING TERMINALS switch to the “Remotely Controlled” position. This will keep the solid state con- tactor open and provide a “cold” electrode until the trig- gering device (Amptrol or Arc Start Switch) is pressed.

COMMANDER 300