Abnormal Open Circuit Dc Weld Voltage Waveform - Lincoln Electric RANGER SVM148-B Service Manual

F-45

ABNORMAL OPEN CIRCUIT DC WELD VOLTAGE WAVEFORM

HIGH IDLE - NO LOAD - OUTPUT CONTROL AT MAXIMUM
TROUBLESHOOTING & REPAIR
ONE OUTPUT DIODE NOT FUNCTIONING
50 volts
This is NOT the typical DC (+) output
voltage waveform. One output diode
is not functioning. Note the "gap" in
the waveform. One output diode was
disconnected to simulate an open or
non-functioning output diode. Each
vertical division represents 50 volts
and each horizontal division repre-
sents 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
RANGER 300 D AND 300 DLX
0 volts
5 ms
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