Miller Maxstar 300 DX Owner's Manual page 37

4-12. AC Waveshape (Dynasty Models Only)
4-13. Spot Time Control (Reconfigured RMT 2T HOLD Output Selection) (All Models)
SPO
3
1
1.0
2
1
3
Or
Or Or
2
1 AC Waveshape
2 Encoder Control
3 Ammeter
Turn encoder (see Section 4-2) to
set appropriate value for active AC
Waveshape parameter. Value se-
lected is shown on the ammeter
(see Section 4-4).
See Section 4-16 for all AC Wave-
shape parameter ranges.
Balance: AC Balance Control is
enabled only if AC TIG process is
selected. Use control to set per-
centage of time polarity is electrode
negative.
Application:
When welding on oxide forming ma-
terials such as aluminum or magne-
sium, excess cleaning is not neces-
sary. To produce a good weld, only
a minimal amount, approximately a
0.10 in (2.5mm) of etched zone
along the weld toes is required.
Joint configuration, set-up, process
variables, and oxide thickness may
affect setting.
AC Frequency: AC Frequency
Control is enabled only if AC TIG
process is selected. Use control to
set AC frequency (cycles per sec-
ond).
Application:
AC frequency controls bead width
and directional control. As AC fre-
quency decreases, weld bead/
puddle gets wider. As AC frequency
increases, weld bead/puddle be-
comes narrower and the arc be-
comes more focused. Travel speed
can increase as AC frequency in-
creases.
1 Spot Time Meter Display
Select Spot function according to
Section 4-19C.
2 Amperage Switch Pad
3 Encoder Control
Set spot parameters as follows:
Press Amperage switch pad once
(meter A LED turns on) and turn En-
coder to set spot amperage. Press
Amperage switch pad again, (meter
S LED lights) and turn Encoder to
set spot time (.1–25 seconds). Fac-
tory default setting is 1 second.
Application: To provide a timed
weld. Used for tacking, and thin
sheet joining.
OM-2222 Page 31