[Bullfrogg0]

I have a 1976 Miller Dialarc 250 and it's tripping the breaker when in the "off" position. As long as it's running or "on" it won't trip the breaker, but as soon as I turn it off, poof, tripped breaker. I've had this welder for almost a year now and this just started happening to me yesterday. I'm at a loss as nothing has changed. I haven't moved it, changed anything on it and even checked the plug to see if any wires were touching inside and everything appears normal.

Any ideas?

Thanks,
Preston

[Poland308]

The switch might be going bad. Sometimes old switch bodies get brittle and can allow a short across legs or to ground. If you unplug it you can ohm it out from the cord end. As you switch the switch you should be able to tell pretty easily what’s going on.