B-6

OPERATION

B-6

 

 

 

6.PEAK CURRENT CONTROL

Presets the maximum welding current the machine will produce, from 2 through 400 amps. The preset current is displayed on the digital ammeter when you are not welding.

NOTE: The ammeter display is an indicator of the preset current. Actual welding current will be slightly different.

If you use an Amptrol, it will control the current from 2 amps up to the current preset by the Peak Current control. See the section, “Hand and Foot Amptrol Operation” for proper use of hand and foot Amptrols.

If pulsing, the peak current is the current set and controlled by the Peak Current control (Item 6) and the Amptrol.

7.VOLTS/AMPS SWITCH

A two-position, spring-loaded toggle switch for selecting either arc voltage or welding current/pre- set current to be displayed on the digital meter.

To read the arc voltage, you must hold the switch in the “Volts” position. This spring-loaded switch always returns to the “AMPS” position when released.

8.AC WAVE BALANCE

This control is active only in AC TIG mode. It con- trols the amounts of positive and negative current in the AC output. It has no effect on stick or DC TIG welding.

AUTO BALANCE: This setting provides automat- ic adjustment of the AC wave balance, and it is the preferred balance setting for most welding condi- tions. This setting gives the ideal amount of clean- ing and penetration, based on the welding current output. When the control is set to the Auto Balance position, the Auto Balance LED (Item 9) will light. This feature operates only in the AC TIG mode.

For those procedures when manual adjustment of the Wave Balance control is necessary, use the following as a guide:

BALANCED: The amounts of positive and negative are the same.

CLEANING (Below “3” on the dial): Provides more positive current than negative current. Since the positive current produces the “cleaning” or oxide removal on aluminum, this setting is used for heavily oxidized aluminum.

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CAUTION

Use only the amount of “cleaning” required. Greater amounts of positive current will heat the tungsten more and possibly cause it to melt or “spit.” Also, the arc is usually more flared and less stable with more positive “cleaning” current.

PENETRATION (Above “3” on the dial): Provides more negative current than positive current. The “cleaning” effect will be reduced, but the arc plas- ma will be more concentrated and more easily directed to where the heat is needed. The reduced amount of positive current allows the tungsten to run cooler at a given current than when set balanced.

In general, use just enough “cleaning” to remove oxides and to give good wetting of the puddle.

9.AUTO BALANCELED

Illuminates only when the Auto Balance function is active. The welder must be in the AC TIG mode, with the AC Wave Balance control fully clockwise.

10.AFTERFLOW

This control adjusts the amount of time the gas and water valves stay open after the end of a weld. Minimum time is approximately 5 seconds; maxi- mum is approximately 55 seconds. Use enough Afterflow time to protect the hot tungsten with gas shielding until it cools. Too short of a time will cause the tungsten to oxidize and become conta- minated. When in doubt, set a longer time, then reduce it to a time that still gives good protection.

PREFLOW

All machines have an adjustable Preflow time.

If a new weld is started during the Afterflow time of a previous weld, the Preflow time is bypassed, since gas shielding is already present. This allows new welds to start immediately, with no preflow delay.

11.ARC FORCE

This control is active only in Stick mode. It con- trols the amount of current added to the welding current when the electrode shorts to the work.

At Minimum, no extra short circuit current is added. The arc will be softer and will have less spatter but may be more prone to sticking.

SQUARE WAVE TIG 355

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Lincoln Electric IM467-B Peak Current Control, VOLTS/AMPS Switch, AC Wave Balance, Auto Balance LED, Afterflow, Preflow