MIG Varistor

[glen48]

Hi
I have a Ozito 135 Amp mig 220V has a blown varistor with no ID only thing I can tell you it is green about the size of a small coin and thin, just interested in getting it going so any idea..
Much involved in upgrading?? seem to me the WFM stops for a split second so I end up with a bad weld..
thanks

 

[dr pepper]

The wirefeed shouldnt be affected by the varistor, its there primarily to prevent noise from getting back onto the mains caused by switching transients.
I couldnt just guess a value, depends on many factors, can you get a diagram, or is there anything at all visible on the old part.

 

[tcmtech]

Being across the main bridge rectifier assy it's likely only a 100- 200 volt device. A quick and rather effective fix is to install .1 uf 200 volt (or higher voltage rated) non polar capacitors across the two plates plus one across each diode.

Best guess is its one of these.

**broken link removed**