Upper Case Front Control Panel

B-5		OPERATION	B-5

The upper case front panel controls are used for man- ual TIG and stick welding.

1.CURRENT CONTROL SWITCH A two-position toggle switch:

LOCAL (PANEL): Current is controlled by the machine settings; remote Amptrol has no affect on current.

REMOTE: Current is controlled by a remote Amptrol up to the current set on the machine.

2.MODE SWITCH

A two-position toggle switch:

STICK: For stick electrode welding (SMAW), this position makes the Stick Arc Force control active. This switch locks out high frequency, the gas and water valves, and the AC Wave Balance control. The STICK position also locks out the Spot Time, Start Time and Crater Fill controls. The Pulse con- trols are locked out except when an Arc Start switch connected to the Remote receptacle is closed.

TIG: For TIG welding (GTAW), this position locks out the Stick Arc Force control. It makes all other controls active. To start and stop the welding sequence and to get output current, an Amptrol or Arc Start switch must be used when this switch is in the TIG position.

3.2-STEP/4-STEP SWITCH

A two-position toggle switch: (Locked out in the STICK mode.)

2-STEP: For use with an Arc Start switch or an Amptrol remote current control. The Arc Start switch must be held down during the entire weld cycle. Pressing the Arc Start switch starts the Preflow cycle, and releasing the switch ends the weld cycle.

NOTE: If the Crater Fill switch (Item 16) is ON, welding will continue after the Arc Start switch is released. (See Crater Fill controls.)

4-STEP: For use with an Arc Start switch only. The Arc Start switch must be pressed and released to start the weld cycle. Pressing and releasing the Arc Start switch a second time ends the weld cycle. This eliminates the need to continuously hold down the Arc Start switch during a weld. If the Preflow timer (Item 12) is being used, the Arc Start switch must be held down during the Preflow time. The Arc switch can be released once an arc is established.

NOTE: If the Crater Fill switch (Item 16) is ON, welding will continue after the Arc Start switch is pressed and released the second time. (See Crater Fill Controls.)

NOTE: If the arc goes out while welding in the 4- Step mode, the machine will try to re-establish an arc for a period of two seconds. The output con- tactor will remain closed, and the High Frequency, if in the Start Only or continuous mode, will be activated. If an arc does not re-establish within two seconds, the weld cycle is automatically ended.

4.HIGH FREQUENCY SWITCH

A three-position toggle switch: (Locked out in STICK mode).

CONTINUOUS: High frequency will come on after the gas Preflow time and remain on until the weld is stopped.

START : High Frequency will come on for 1-2 sec- onds after an arc is established, then go off. (When AC TIG welding, the high frequency will stay on until after the Start period and come on again during the Crater Fill period.)

OFF: No high frequency.

5.DIGITAL VOLTMETER/AMMETER

Displays the output voltage of the welder when the VOLTS/AMPS switch (Item 7) is held in the “VOLTS” position.

When the VOLTS/AMPS SWITCH IS IN THE “AMPS” position, this display functions as an ammeter.

When you are not welding, the ammeter displays the value preset by the Peak Current control.

When you are not welding and the Start Current Display pushbutton is pressed, the ammeter will display the preset Start (Item 14). (See Start Controls)

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

While you are welding, the ammeter displays the actual welding current. The ammeter is accurate within ±3% of its reading or ±2 amps, whichever is greatest. The ammeter displays RMS current. (RMS current is the actual “heating value” of the arc.) NOTE: Some types of ammeters will not accurately read true RMS currents, particularly when AC TIG welding aluminum. AC only amme- ters may read as much as 40% low when measur- ing AC TIG welding currents.

SQUARE WAVE TIG 355

OPERATION