If the connector only has 3 pins, it sounds like they're using the rheostat to turn the arc/gas solenoid on and off.
Originally Posted by John Stevenson
So three terminals should be the rheostat: two ends of the resistor and the wiper. So buzz-out the lines while you vary the foot pedal. You would think the wiper would be the middle terminal
Doesn't your manual have the pinout for the pedal?
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