Typical Scr Gate Voltage Waveform - Lincoln Electric WIRE-MATIC 255 SVM 119-A Service Manual

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TYPICAL SCR GATE VOLTAGE WAVEFORM

This is a typical SCR gate pulse voltage
waveform. The machine was in an open cir-
cuit condition (no load) and operating prop-
erly. Note that each vertical division repre-
sents 2 volts and each horizontal division
represents 5 milliseconds in time.
Note: Scope probes connected at Plug J3
on the control board. The (+) probe to lead
G2, and the (-) probe to lead 204.
TROUBLESHOOTING & REPAIR
WIRE-MATIC 255
SCOPE SETTINGS
Volts/Div . . . . . . . . . . . . . . . . . .2 V/Div.
Horizontal Sweep . . . . . . . . . .5 ms/Div.
Coupling . . . . . . . . . . . . . . . . . . . . .DC.
Trigger . . . . . . . . . . . . . . . . . . .Internal.
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