Lift-Arce And Hf Tig Start Procedures - Miller Maxstar 300 DX Owner's Manual

9-3. Lift-Arc And HF TIG Start Procedures
Lift-Arc Start Method
OM-2222 Page 62
1
1 – 2
"Touch"
Seconds
Do NOT Strike Like A Match!
2
Lift-Arc Start
When Lift-Arct button light is On,
start arc as follows:
1 TIG Electrode
2 Workpiece
Touch tungsten electrode to work-
piece at weld start point, enable out-
put and shielding gas with torch trig-
ger, foot control, or hand control.
Hold electrode to workpiece for
1-2 seconds, and slowly lift elec-
trode. Arc is formed 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.
Application:
Lift-Arc is used for the DCEN or AC
GTAW process when HF Start
method is not permitted, or to re-
place the scratch method.
HF Start
When HF Start button light is On,
start arc as follows:
High frequency turns on to help
start arc when output is enabled.
High frequency turns off when arc is
started, and turns on whenever arc
is broken to help restart arc.
Application:
HF start is used for the DCEN
GTAW process when a non-con-
tact arc starting method is required.