Lincoln Electric IDEALARC DC-655 Service Manual page 88

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TYPICAL OUTPUT VOLTAGE WAVEFORM - MACHINE LOADED
TROUBLESHOOTING & REPAIR
CONSTANT VOLTAGE MIG MODE
20 volts
This is the typical DC open circuit voltage wave-
form generated from a properly operating
machine. Note that each vertical division repre-
sents 20 volts and that each horizontal division
represents 2 milliseconds in time. The machine
was loaded with a resistance grid bank. The
grid bank meters read 650 amps at 44 VDC.
Note: Scope probes connected at machine out-
put terminals: (+) probe to positive terminal, (-)
probe to negative high inductance terminal.
SCOPE SETTINGS
Volts/Div.....................20V/Div.
Horizontal Sweep.....2 ms/Div.
Coupling ............................DC
Trigger .........................Internal
IDEALARC DC-655
0 volts
2 ms
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