Lincoln Electric IM986 manual Pulse Welding, Non Synergic CV

B-8 OPERATION 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

1.50with 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.

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 -10.0 to +10.0 with a 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