Operation – Lincoln Electric POWER WAVE SVM173-A User Manual

Page 27

STT WELDING

The pictures illustrate the wave shape of current for the
process. They are not drawn to scale, and are intend-
ed only for the purpose of showing how the variables
affect the waveform.

Trim in the STT mode adjusts the tailout and back-
ground portion of the waveform. Trim values greater
than 1.0 add more energy to the weld and make the
weld puddle hotter; trim values less than 1.0 reduce
energy to weld. A nominal value of 1.0 will work for
most applications. (See Figure B.4.)

B-9

OPERATION

POWER WAVE 455M/MSTT

Current

Time

Trim 1.50

Trim 1.00

Trim 0.50

FIGURE B.4 – STT TRIM CONTROL CHARACTERISTICS

Current

Time

Wave Control +10.0

Wave Control -10.0

Wave Control 0.00

FIGURE B.5 – STT WAVE CONTROL CHARACTERISTICS

For most programs, peak current is adjusted by wave
control values. A value of +10.0 maximizes the peak
current, while a wave control of -10.0 minimizes peak
current. In general, the peak current is proportional to
torch arc length. (See Figure B.5.)

NOTE: The ranges on Wave Control and Trim are

dependent on the weld programs. The values
shown are typical ranges.