Miller Multimatic 220 AC/DC Quick Reference page 2

Tungsten Selection and Prep
Tungsten Type Application Notes
Good all-around tungsten for
2% Cerium
both AC and DC welding.
1.5 /2% Lanthanum
Commonly used for DC welding,
2% Thorium
not ideal for AC.
PURE TUNGSTEN (green) is NOT recommended for inverters!
For best results in most applications use a sharpened cerium
or lanthanum electrode for AC and DC welding.
Tungsten Preparation:
Sharpen tungsten for AC and DC welding.
CORRECT INCORRECT
Ideal Preparation — Stable Arc Wrong Preparation — Wandering Arc
Straight Ground
Stable Arc
Blunt Tip
Grinding
Grinding
Wheel
Wheel
Note: Do not use wheel for other jobs or tungsten can become contaminated.
Tip: Blunting the tip of the electrode is sometimes done to help maintain consistent geometry and resist
tungsten erosion. This is especially helpful in AC when melt-back of the tungsten electrode is common.
Pulsed TIG Controls
The Pulsed TIG function switches the amperage from a high (peak) to a low (background) at a set rate (PPS).
Pulsing can reduce heat input by lowering the average amperage, increasing control of the weld puddle,
penetration and distortion. The following parameters can be adjusted for desired results:
Low-Speed Pulse
1 to 10 pulses per second (PPS) will produce a
distinct ripple pattern in the weld bead. Can be
used to time ller addition, reduce distortion and
improve control.
Distinct ripple pattern
Tip: Begin welding at factory default settings of 100 PPS, 40% peak and 25% background amps.
Adjust the frequency (PPS) to change width and appearance.
MillerWelds.com
# 283817 © 2018 Miller Electric Mfg. LLC
Diameter Amp Range
0.020" 5–20
0.040" 10–80
1/16" 10–150
3/32" 60–250
1/8" 100– 400
5/32" 160–500
3/16" 190–750
1/4" 325–1100
Note: Only 1/16" or 3/32"
tungsten can be selected
when using Auto-Set.
IDEAL GRIND ANGLE RANGE
15˚ to 30˚
Radial Ground
Arc Wander
AC EFFECT
Pointed Tip
Slight meltback
of electrode tip
High-Speed Pulse
100 pulses per second (PPS) and higher helps to
focus the arc for increased stability, penetration and
travel speed. Increased puddle agitation improves
weld microstructure.
Focused arc
increases Narrow bead and
travel speed heat affected
and penetration zone
AC Waveshape Controls
Feature Setting
AC Balance
AC Balance controls arc cleaning
60%
action. If oating black spots
appear in the puddle, the
balance setting is too high.
Turn the balance down until
puddle becomes clear.
75%
AC Frequency
Controls the width of the arc
60 Hz
cone. Increasing the AC
Frequency provides a more
focused arc and increased
directional control.
Note: Decreasing the AC
Frequency softens the arc and
broadens the weld puddle for a
wider weld.
120 Hz
TIG Post ow Control (Menu 12 of 12)
1 1
2
TIG POSTFLOW
12 / 12
CONTROL
AUTO
TURN RIGHT ENCODER
TO ADJUST SETTING
3
Arc Effect Weld Effect
Increases electrode Wider bead and
cleaning action
balling action
Cleaning
Reduces balling, Narrow bead with
helps maintain reduced cleaning
point of electrode
Cleaning
Wider pro le ideal
for buildup work
Narrower pro le
for llet welds
1
Access (and Exit) Setup Menus
Simultaneously press and release
left-side – button and right-side + button.
2
Navigate to TIG Post ow Control Menu
Use right-side –/+ buttons to select menu 12.
3
Adjust TIG Post ow
Use right knob to adjust. The range is
AUTO–25 seconds. After completing
selection, exit setup menus (see step 1).
Bead
Bead
Bead
Visible oxide
removal (etching)
Bead
Visible oxide
removal (etching)