Powermax 1250 G3 - Problem with internal power surge, and "pop" of household breaker

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Hello everyone. Have bought Powermax 1250 G3 plasma cutter and trying to make it Live again for my CNC plasma project.I would need some help if someone can answer, what numbers inrush current limiters mine has? because those were blown out and cant identify. If someone has it please share the knowledge or even a photo, thanks in advance.Current state of machine, IBGT was burnt(already received part for exchange, need to inspect some more resistors and order correct thermistors-inrush current limiters)





Reply:Put a heading on here...Questions for Jim Colt. He is the go to Hypertherm man.
Reply:I can't help, however technical service at Hypertherm can. [email protected]  or 1 800 643 9878  Jim Colt
Reply:Sooner or later that is what you get. Hate to see it but I call " too costly to repair"
Reply:the pcb looks fried to me. check the transistor on the heat sink in the top corner of your picture.if shorted. you will have to replace the pcb and both IGBT units.there is a green inductor that lives to the left of the right side IGBT gate leads. Don't see it.when it gets burnt and the transistor fails. the PFC circuit has failed. It takes out the pcb and both IGBTs even if they test ok. The PFC circuit is what makes this unit an auto line. self adjusting. from the picture the pcb you have is what I call a gen 2 pcb. This failure seems to happen when operated on 230 volt single phase power here in the the US. let me back up. I see you have  filter pcb which tells me you are in Europe a CE country.those units work a little differently. here in USA our machines can run from 200 to 600 volts.CE units are 200 or 400 volt units I think. Might be why the green inductor is missing.In general when inrush resistors blow up, it is because  the device that bypasses them has failed. It can be a relay or a power transistor. The inrush resistors are only designed to handle the current to charge up the DC buss caps then get switched out. if cut current goes through them they die. if a buss cap has shorted they can fail.
Reply:The CE units (1250) operate on single phase only, and require different power line filtration.   Jim Colt  

Originally Posted by ccawgc

the pcb looks fried to me. check the transistor on the heat sink in the top corner of your picture.if shorted. you will have to replace the pcb and both IGBT units.there is a green inductor that lives to the left of the right side IGBT gate leads. Don't see it.when it gets burnt and the transistor fails. the PFC circuit has failed. It takes out the pcb and both IGBTs even if they test ok. The PFC circuit is what makes this unit an auto line. self adjusting. from the picture the pcb you have is what I call a gen 2 pcb. This failure seems to happen when operated on 230 volt single phase power here in the the US. let me back up. I see you have  filter pcb which tells me you are in Europe a CE country.those units work a little differently. here in USA our machines can run from 200 to 600 volts.CE units are 200 or 400 volt units I think. Might be why the green inductor is missing.In general when inrush resistors blow up, it is because  the device that bypasses them has failed. It can be a relay or a power transistor. The inrush resistors are only designed to handle the current to charge up the DC buss caps then get switched out. if cut current goes through them they die. if a buss cap has shorted they can fail.