Troubleshooting & repair, 2 volts 5ms ch1, Typical scr gate voltage waveform caution – Lincoln Electric SQUARE WAVE TIG 255 SVM100-A User Manual
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SQUARE WAVE TIG 255
F-37
TROUBLESHOOTING & REPAIR
TYPICAL SCR GATE VOLTAGE WAVEFORM
CAUTION
HIGH VOLTAGE / HIGH FREQUENCY can damage test equipment.
• Perform all voltage and waveform checks with high frequency circuit OFF.
_____________________________________________________________________
0 volts
2 volts
5ms
CH1
This is the typical SCR gate pulse voltage
waveform. The machine was in an open
circuit condition (no load) and operating
properly. Note that each vertical division
represents 2 volts and that each horizontal
division represents 5 milliseconds in time.
Note: Scope probes connected at SCR
gate and cathode: (+) probe to gate, (–)
probe to cathode.
Volts/Div..................................2 V/Div.
Horizontal Sweep .................5 ms/Div.
Coupling .........................................DC
Trigger .....................................Internal
SCOPE SETTINGS