Pilotarc IGBT broken?

[Harrstein]

Hey guys

I have a Combiarc 200 which is basically a rebranded powerpro 205.
And its pilotarc doesnt work

I checked the usual stuff like fuse and continuity of the torch. It would still weld with tig.

So this makes me think that the pilotarc igbt has ceased to be. How can I check this?

Thanks in advance for the help.

[Rambozo]

Measure it.
Also check the transfer circuit. Some are solid state, but others use a relay, that could have the contacts welded.
Just because it looks similar, it might be totally different inside. If you understand how they work, it's pretty easy to troubleshoot. However, many Chinese factories grind off all the part numbers of components, so that makes it hard to mach replacement parts if you don't have any measurements from when it was working.

[performance]

Can you scratch start the plasma torch to start the arc.

[Harrstein]

I wasn't able to strike start it.

When i pull the trigger a single hiss of air is heard. Then its quiet and when I release the button another hiss of air.

[performance]

Make sure it is in 2T or normal trigger mode, and not latch mode. If it is then likely there is a unit issue internally.