Abnormal Open Circuit Weld Voltage Waveform - Lincoln Electric WELDANPOWER SVM 113-A Service Manual

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ABNORMAL OPEN CIRCUIT WELD VOLTAGE WAVEFORM

HIGH IDLE – NO LOAD – OUTPUT CONTROL AT MAXIMUM
TROUBLESHOOTING & REPAIR
50 volts
This is not the typical DC output
voltage waveform. Note the "gap" in
the waveform. One output diode was
disconnected to simulate an "open"
diode. Each vertical division repre-
sents 50 volts and that each horizon-
tal division represents 5 milliseconds
in time.
Note: Scope probes connected at
machine output terminals.
SCOPE SETTINGS
Volts/Div.....................50V/Div.
Horizontal Sweep.....5 ms/Div.
Coupling ............................DC
Trigger .........................Internal
WELDANPOWER 125
CH1
0 volts
5 ms
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