Lincoln Electric power wave c300 Operator's Manual page 33

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STEEL AND STAINLESS SYNERGIC GMAW-P (PULSED MIG) WELDING
When pulse welding, the power source primarily regu-
lates the arc current, not the arc voltage. During a
pulsing cycle, arc current is regulated from a low
background level to a high peak level and then back
down to the low background level. The average arc
voltage increases and decreases as the average arc
current is increased or decreased. The peak current,
back ground current, rise time, fall time and pulse fre-
quency all affect the average voltage. Since the aver-
age voltage for a given wire feed speed can only be
determined when all the pulsing waveform parameters
are known, a unit less value called "trim" is used for
adjusting the arc length.
ULTIMARC™CONTROL (See Figure B.6)
UltimArc™ Control adjusts the focus or shape of the arc.
UltimArc™ Control is adjustable from -10.0 to +10.0 with
a nominal setting of 0.0. Increasing the UltimArc™
Control increases the pulse frequency and background
current while decreasing the peak current.
The Power Wave utilizes adaptive control to compensate for
®
changes in the electrical stick-out(distance from the contact tip to
the work piece) while welding. The Power Wave waveforms are
optimized for a 5/8" to 3/4" stick out depending on the wire type and
wire feed speed.
OPERATION
Trim adjusts the arc length and ranges from 0.50 to
1.50 with a nominal value of 1.00. Increasing the trim
value increases the arc length. Decreasing the trim
value decreases the arc length.
Pulse welding modes are synergic; using wire feed
speed as the main control parameter. As the wire
feed speed is adjusted, the power source adjusts the
waveform parameters to maintain good welding char-
acteristics. Trim is used as a secondary control to
change the arc length for material conditions or indi-
vidual preference. (See Figure B.5)
FIGURE B.5
This results in a tight, stiff arc used for high speed sheet
metal welding. Decreasing the UltimArc™ Control
decreases the pulse frequency and background current
while increasing the peak current. This results in a soft
arc good for out of position welding.
FIGURE B.6
The adaptive behavior supports a range of stick outs
from approximately 1/2" to 1-1/4". At low or high wire
feed speeds, the adaptive range may be less due to
physical limitations of the welding process.
POWER WAVE C300
®
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