Lift-Arc Tig Procedure - Miller XMT 400 Owner's Manual

6-4. Lift-Arc TIG Procedure

Notes
1
1 − 2
"Touch"
Seconds
Do NOT Strike Like A Match!
With Process Switch in the Lift-Arc
TIG position, start an arc as follows:
1
2
Touch tungsten electrode to work-
piece at weld start point, hold
electrode to workpiece for 1-2
seconds, and slowly lift electrode.
2 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.
TIG Electrode
Workpiece
Ref. S-156 279
OM-217769 Page 25