Section 4 - Operation; Function Of Controls; Welding Power Source - Miller Electric MMP Owner's Manual

4-1. Function Of Controls

4
1

4-2. Welding Power Source

OM-814 Page 6
SECTION 4 – OPERATION
1
Controls
3
4
2
Time
Matching Waveform
2
3
1
1 Peak Current Control
Use control to select peak current
level during pulsed welding. Peak
current level is defined as a
percentage (25 – 100%) of maxi-
mum output current of the welding
power source in CC mode.
Peak current is the high pulse of
welding current. Peak current melts
the welding wire and forms a drop-
let. The droplet is forced into the
weld puddle.
2 Pulse Width Control
Use control to select length of peak
current pulse. The scale around the
control is in milliseconds.
Pulse width is the time spent at
peak current. This time must be
long enough to form a droplet of
welding wire. The stiffness or fluid-
ity of the molten weld puddle is con-
trolled by pulse width.
3 Pulse Frequency Control
Use control to select number of
peak current output pulses per
second. The scale around the
control is in pulses per second.
A pulse frequency of 60 pulses per
second (pps) means 60 pulses of
peak current are produced each
second.
4 Background Current Control
Use control to select background
current level. The background
current level is defined as a
percentage (3 – 25%) of maximum
output current of the welding power
source in the CC mode.
Background current is the low weld
current. Background current pre-
heats welding wire and maintains
the arc. When background current
is too low, the arc is unstable and
hard to maintain.
Every month check labels, cord,
and plug for damage.
Ref. SC-158 109-A / Ref. S-0259
5 Welding Power Source
Set Output (Contactor) switch in
Remote position.
Set Mode switch in GTAW (CC) po-
sition.
Set Amperage/Voltage Control
switch in Remote 17 position.
Turn Arc Control/Inductance con-
trol to minimum.