Troubleshooting & repair, Abnormal output voltage waveform - machine loaded – Lincoln Electric IDEALARC SVM136-A User Manual
Page 71
TROUBLESHOOTING & REPAIR
F-31
F-31
IDEALARC CV-400
This is NOT the typical DC output
voltage waveform. One output SCR
is not functioning. Note the “ripple”
in the waveform. One SCR gate is
disconnected to simulate an open or
non-functioning output SCR. Each
vertical division represents 20 volts
and each horizontal division repre-
sents 5 milliseconds in time. The
machine was loaded with a resis-
tance grid bank. The CV-400 meters
read 400 amps at 36 VDC.
Note: Scope probes connected at
machine output terminals: (+) probe
to positive terminal, (-) probe to neg-
ative terminal.
SCOPE SETTINGS
Volts/Div.....................20V/Div.
Horizontal Sweep.....5 ms/Div.
Coupling ............................DC
Trigger .........................Internal
ABNORMAL OUTPUT VOLTAGE WAVEFORM - MACHINE LOADED
ONE OUTPUT SCR NOT FUNCTIONING
0 volts
5 ms
20 volts
CH1