Lincoln Electric IDEALARC DC-600 Service Manual page 93

F-49
TYPICAL SCR GATE VOLTAGE WAVEFORM
TROUBLESHOOTING AND REPAIR
CONSTANT VOLTAGE INNERSHIELD
MAXIMUM OUTPUT SETTING - NO LOAD
2 volts
This is the typical SCR gate pulse voltage
waveform. The machine was in an open cir-
cuit condition (no load) and operating proper-
ly. Note that each vertical division represents
2 volts and that each horizontal division rep-
resents 5 milliseconds in time.
Note: Scope probes connected at SCR gate
and cathode:
(-) probe to cathode.
SCOPE SETTINGS
Volts/Div.......................2V/Div.
Horizontal Sweep .....5 ms/Div.
Coupling.............................DC
Trigger.........................Internal
IDEALARC
5ms
(+) probe to gate,
® DC-600
F-49
CH1
0 volts