Miller Electric XMT 350 CC/CV - Manual (Page 26)

OM-2247 Page 22
5-4. Lift-Arc TIG Procedure
With Process Switch in the Lift-Arc
TIG position, start an arc as follows:
1
TIG Electrode
2 Workpiece
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.
1
1 − 2
Seconds
“Touch”
Do NOT Strike Like A Match!
2
Ref. S-156 279
5-5. Stick Start Procedure
With Stick selected, start arc as fol-
lows:
1
Electrode
2 Workpiece
3 Arc
Drag electrode across workpiece
like striking a match; lift electrode
slightly after touching work. If arc
goes out electrode was lifted to high.
If electrode sticks to workpiece, use
a quick twist to free it.
Low OCV Stick
The unit can be optionally config-
ured for low open circuit voltage
(OCV) operation. When the unit is
configured for low OCV operation
only a low sensing voltage (approxi-
mately 15 VDC) is present between
the electrode and the workpiece
prior to the electrode touching the
workpiece. Consult a Factory
Authorized Service Agent for infor-
mation regarding how to configure
the unit for low OCV stick welding
operation.
1
2
3