Theory and Applications
Applications
3
3-5
Problem Symptom
Preheat problems
Waveform intensity continues to increase over
the first few cycles.
Arcing
Waveform exhibits sharp rises and spikes with
a duration of 10 to 1000 microseconds.
Overshoot Problems
Waveform exhibits overshoot on the first 2 or
3 pulses (3 phase machine).
Contactor Bounce
Waveform peaks contain noise or smaller
peaks riding on major peaks.
Rectifier Imbalance
Relative peak heights are different and
repeatable (i.e., one high and one low, or, in a
three phase machine, high-medium-low, high-
medium-low, high-medium-low.)
Load Effects
Waveform exhibits drooping during a long
exposure.
