Lincoln Electric SVM100-A TIG Welding Sequence Operation 2-STEP Mode, Square Wave TIG 255 12/95

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B-9					OPERATION
						TABLE B.2					(2)
			TYPICAL CURRENT RANGES (1) FOR TUNGSTEN ELECTRODES
						AC				Approximate Argon
											Gas Flow Rate
		DCEN ( - )	DCEP ( + )	Unbalanced Wave			Balanced Wave				C.F.H. (1/min.)
Tungsten						1%, 2%		1%, 2%
Electrode		1%, 2%	1%, 2%			Thoriated		Thoriated						TIG Torch
Diameter		Thoriated	Thoriated	Pure		Tungsten	Pure	Tungsten				Stainless		Nozzle
in. (mm)		Tungsten	Tungsten	Tungsten		Zirconiated	Tungsten	Zirconiated		Aluminum		Steel		Size (4), (5)
.010	(.25)	2-15	(3)	2-15		2-15	2-15	---	3-8		(2-4)	3-8	(2-4)	#4, #5, #6
0.020	(.50)	5-20	(3)	5-15		5-20	10-20	5-20	5-10		(3-5)	5-10	(3-5)
0.040	(1.0)	15-80		10-60		15-80	20-30	20-60	5-10		(3-5)	5-10	(3-5)
			(3)
1/16	(1.6)	70-150	10-20	50-100		70-150	30-80	60-120	5-10 (3-5)			9-13 (4-6)		#5, #6
3/32	(2.4)	150-250	15-30	100-160		140-235	60-130	100-180	13-17 (6-8)			11-15 (5-7)		#6, #7, #8
1/8	(3.2)	250-400	25-40	150-210		225-325	100-180	160-250	15-23 (7-11)			11-15 (5-7)
5/32	(4.0)	400-500	40-55	200-275		300-400	100-240	200-320	21-25 (10-12)			13-17 (6-8)		#8, #10
3/16	(4.8)	500-750	55-80	250-350		400-500	190-300	290-390	23-27 (11-13)			18-22 (8-10)
1/4	(6.4)	750-1000	80-125	325-450		500-630	250-400	340-525	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 gasses.

(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 with- stand high temperatures and high duty cycles.

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TIG WELDING SEQUENCE OF

OPERATION (2-STEP MODE)

In TIG 2-Step Mode the welding arc is established by depressing the Arc Start Switch or Amptrol (Step 1). Output continues as long as the switch or Amptrol is depressed. Releasing the switch or Amptrol (Step 2) turns off the arc. Hence the name 2-Step Mode.

1.Connect an Arc Start Switch or an Amptrol to the Remote Receptacle.

2.Turn on the welder, gas supply and water supply (if so equipped). The Control Panel Display and red LEDS will illuminate when the power is on.

3.Select the TIG 2-Step Weld Mode.

4.Select Local (if using an Arc Start Switch) or Remote (if using an Amptrol) current control. Set the output current using the Amps Up/Down keys. The output current setting will be displayed on the Ammeter.

5.Select Continuous High Frequency if welding with AC polarity, or Start Only High Frequency if welding with DC- polarity. High Frequency Off can be used for scratch start welding.

6.Select AC or DC- electrode polarity. See Table B.1.

7.If welding with AC polarity, select Auto Balance™. This gives the optimum ratio between cleaning and penetration, automatically adjusted for the output current. If manual adjustment of the AC Wave Balance is desired, select Manual Balance, and adjust the wave balance with the Cleaning and Penetration keys. See the Advanced Features section for more information on setting and using the AC Wave Balance.

8.Select TIG Pulser On or Off. If the TIG Pulser is on, adjust the pulse frequency with the Pulses Per Second Up/Down keys. See the Advanced Features section for more information on setting and using the TIG Pulser.

SQUARE WAVE TIG 255 12/95