Breaker Trips AFTER finished welding

The only possibility I can think of is that the wire or panel bus is overheating and the heat eventually conducts to the breaker to overheat it and trip it. Seems pretty unlikely though. I would just try a new breaker first and if it fixes it then file it under "Great Unsolved Mysteries I Have Known". I have a pretty big file of those.

Try a new breaker. I had one act up on me a while ago. It was the only thing that made any sense for my problem. Maybe yours too. Don could also have the answer if the panel is too hot. Use an IR temp gun on that issue.

Hope it helps,

Rob

Fraser Competition Engines Chicago, IL.

Kevin,

Did you try to immediately unplug the machine after you finished welding? If the breaker still trips a few minutes after this, it excludes problems in the machine.

Circuit breakers are mechanical in nature and can go defect though. For a quick and easy solution I would simply replace it and see if it still occurs.

Peter.

Does this machine have the power factor correction option? Power factor correction on transformer machines pushes the idle current WAY up. If the breaker was already warm from welding, the idle current into the power factor correction might be enough to pop the breaker.

Good Luck, Bob