Flat spot, bad arc in middle of pedal travel?

[PeterA]

So I have a dead spot in the middle of my tig foot pedal travel.

What causes this? Is it the main pot. that is driven by the belt?

I read that there is a 47 and 50K pot pedal depending on models. My tig is a 200dx. Safety checked in 2012 reading from a sticker on the back of the machine.

If it is the pot I will replace with another. How many watts are the pots?

[Rambozo]

So I have a dead spot in the middle of my tig foot pedal travel.

What causes this? Is it the main pot. that is driven by the belt?

I read that there is a 47 and 50K pot pedal depending on models. My tig is a 200dx. Safety checked in 2012 reading from a sticker on the back of the machine.

If it is the pot I will replace with another. How many watts are the pots?

Sure sounds like the pot. Probably got dirt in it. You can measure your old one if it's not marked, but there is no problem swapping 47 for 50. There is no real current, so even a 1/4 watt would be fine. The thing to look for is a sealed unit, then it will be the last one you buy. Also there are two tapers, linear and logarithmic. Not sure what is standard, but it should be marked. Also you may prefer one over the other, so I would buy both and see which you prefer. As a temp fix, you can spray contact cleaner in your old one to get back up and running while you wait for the new one.

[PeterA]

I put the meter on it and got these readings.


pins
3-5 anti clockwisw knob, off or on pedal 47.3
3-5 clockwise knob, off or on pedal 2.4

3-4 anti clockwise, off pedal = 0.00, on pedal 02.3
3-4 clockwise, off pedal = 02.3, on pedal 0.00

4-5 clockwise, off pedal = 02.4, on pedal 00.3
4-5 anti clockwise, off pedal = 47.3, on pedal 45.2



Not that really tells anything about the smoothness of operation of the pot, but do these values look normal?