I have a Power Arc 200. It welds fine. The adjustment dial is fine. My problem is the display always changing number. I will try to set it at 125 for example. It will them constantly move from 120 to 125 to 130 and so and so. I can't set it to the amps I want.

I've tried my PowerTIG 250ex machine with my power outlet I use with PA200 and the stick mode of that TIG welder works fine. No changing number.

Any ideas?