Originally Posted by
Jeff9
When I got home from work today, I practiced some more on tig welding. I paid attention to the arc while I manipulated the foot pedal. There was no difference in arc size. Next, I turned the amperage knob to 10 amps, started and arc and manipulated the foot pedal, very little arc even with the foot pedal fully depressed. Then I set the amperage to 100 amps, started an arc, manipulated the foot pedal and no change in the arc size.
Next I shielded the arc from my eyes and watched the amp reading on the machine while I manipulated the foot pedal, the reading dropped 2 amps (from 90 to 88) as soon as I started the arc, but no change from 88 no matter the position of the foot pedal.
I took the top off of the foot pedal to see if the gear was rotating the gear on the potentiometer in the foot pedal, and it does.
Using a multimeter, I check OMHs at terminals 3,4,5 on the plug from the foot pedal. Pushing the pedal down, I got 0 to 19k OHMs between 3 & 4. Pushing the pedal down, I got 19k OHMs to 0 between 4 & 5.
What else should I look for or do?
Thank you for the help,
Jeff9