Troubleshooting & repair – Lincoln Electric IDEALARC DC 1000 SVM123-A User Manual
Page 84
F-44
TROUBLESHOOTING & REPAIR
F-44
ABNORMAL OPEN CIRCUIT VOLTAGE WAVEFORM
CONSTANT VOLTAGE INNERSHIELD
ONE OUTPUT SCR NOT FUNCTIONING
MAXIMUM OUTPUT SETTING
IDEALARC DC-1000
SCOPE SETTINGS
Volts/Div. . . . . . . . . . . . . 50 V/Div.
Horizontal Sweep . . . . . 2 ms/Div.
Coupling . . . . . . . . . . . . . . . . . DC
Trigger . . . . . . . . . . . . . . . Internal
This is NOT the typical DC output volt-
age waveform. One output SCR is not
functioning. Note the “gap” in the wave-
form. One SCR gate is disconnected to
simulate an open or nonfunctioning out-
put SCR. Each vertical division repre-
sents 50 volts and each horizontal divi-
sion represents 2 milliseconds in time.
Note: Scope probes connected at
machine ouput terminals: (+) probe to
positive 1000 amp terminal, (-) probe to
negative terminal.