Lincoln Electric POWER WAVE IM986 Operator's Manual page 34

B-8
Non Synergic CV
In non-synergic modes, the machine behaves like a
conventional power source. The WFS and voltage
are independent adjustments. Therefore, to maintain
the arc characteristics, the operator must adjust the
voltage to compensate for any changes made to the
WFS.
UltimArcTM
UltimArcTM adjusts the apparent inductance of the
wave shape. The UltimArcTM adjustment is similar to
a "pinch" function in that it is inversely proportional to
inductance. UltimArcTM is adjustable from –10.0 to
+10.0 with a nominal setting of 0. Increasing
UltimArcTM results in a crisper, hotter arc.
Decreasing the UltimArcTM provides a softer, colder
arc.
Pulse 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 unitless value called "trim" is used for
adjusting the arc length.
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. Alternately, trim can
be displayed as a quasi-voltage value. This allows the
operator to pre-set an approximate welding voltage
rather than a unitless trim value. The pre-set voltage
is limited based on the process, and provides the
same range of operation as the corresponding trim
value.
OPERATION
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. The Power Wave i400 can also be config-
ured to use amperage as the dominant control para-
meter. In this configuration, as the amperage is
adjusted, the power source selects the appropriate
wire feed speed, and adjusts the waveform parame-
ters to maintain good welding characteristics. In either
case, trim is used as a secondary control to change
the arc length for material conditions or individual pref-
erence.
UltimArcTM adjusts the focus or shape of the arc.
UltimArcTM is adjustable from
nominal setting of 0.0. Increasing the UltimArcTM
increases the pulse frequency and background cur-
rent while decreasing the peak current. This results in
a tight, stiff arc used for high speed sheet metal weld-
ing. Decreasing the UltimArcTM decreases the pulse
frequency and background current while increasing
the peak current. This results in a soft arc good for out
of position welding.
The Power Wave utilizes adaptive control to compen-
sate 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. The adaptive behavior supports a range
of stick outs from approximately ½" 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® i400
B-8
-10.0 to +10.0 with a