Abnormal Open Circuit Weld Voltage Waveform (One Diode Open - Lincoln Electric RANGER SVM120-A Service Manual

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ABNORMAL OPEN CIRCUIT WELD VOLTAGE WAVEFORM
HIGH IDLE – NO LOAD – OUTPUT CONTROL AT MAXIMUM
TROUBLESHOOTING & REPAIR
(HIGH CV MODE)
OUTPUT CAPACITOR BANK NOT FUNCTIONING
50 volts
This is NOT the typical CV output
voltage waveform. The capacitor
bank is not functioning. Note the
"ripple" in the waveform. The capac-
itor bank was disconnected to simu-
late an open or non-functioning
capacitor bank. Each vertical divi-
sion represents 50 volts and each
horizontal division represents 5 mil-
liseconds 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 10-LX
CH1
0 volts
5 ms
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