5-2. Meter Functions For CC/CV Models

.The meters display the actual weld output values for approximately three seconds after the arc is broken.

 

Mode

 

 

Meter Reading At Idle

 

 

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

Scratch Start TIG

 

78.0

 

85

 

 

 

Actual Volts (OCV)

 

Preset Amps

 

 

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

Lift-Arc TIG

 

8.0

 

85

 

 

 

 

 

 

 

 

 

 

(GTAW)

 

 

 

 

 

 

 

 

 

Actual Volts

 

Preset Amps

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

Air Carbon Arc

 

78.0

 

85

 

 

 

Actual Volts (OCV)

 

Preset Amps

 

 

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

TIG (GTAW)

 

 

 

 

85

 

 

 

 

 

Blank

 

Preset Amps

 

 

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

MIG (GMAW)

 

24.5

 

 

 

 

 

 

 

 

 

 

 

 

 

Preset Volts

 

Blank

 

 

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

CC

 

 

 

 

85

 

 

 

 

 

Blank

 

Preset Amps

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

Stick (SMAW)

 

78.0

 

 

85

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Actual Volts (OCV)

 

Preset Amps

 

 

 

 

 

 

 

 

 

 

 

V

 

A

 

Voltage-Sensing

 

78.0

 

 

 

 

 

 

 

 

 

 

Wirefeeder

 

 

 

 

 

 

 

 

Flashes OCV And Preset Volts

 

Blank

 

 

 

 

 

 

 

 

 

 

 

 

5-3. Lift-Arc TIG Procedure For CC/CV Models

1 2

1 − 2

“Touch” Seconds

Do NOT Strike Like A Match!

With Mode switch in the Lift-Arc TIG position, start an arc as follows:

1TIG Electrode

2Workpiece

Touch tungsten electrode to work- piece at weld start point, hold electrode to workpiece for 1-2 seconds, and slowly lift electrode. An arc will form when electrode is lifted.

Normal open-circuit voltage is not present before tungsten electrode touches workpiece; only a low sensing voltage is present between electrode and workpiece. The solid-state output contactor does not energize until after electrode is touching workpiece. This allows electrode to touch workpiece with- out overheating, sticking, or getting contaminated.

Ref. S-156 279

OM-2252 Page 23

Page 27
Image 27
Miller Electric NT 450, NT 500 manual Meter Functions For CC/CV Models, Lift-Arc TIG Procedure For CC/CV Models