xmt 304 stick mode problem

[doubledoor]

can you recommend any places that rebuild them?

[cruizer]

Would be one of the pulse transformers. This board you can send out for rebuild

[doubledoor]

I thick something is shot on my top board and that's causing all the problems.

[doubledoor]

Yes changed them both with new ones from miller. Original help7 problem would go away when front igbt was unplugged. So I thought new ones would fix the problem.

[cruizer]

We're both Igbts changed Out? Don't really want to play with the tunnel transformers. Quite the nightmare there. As for the pickups they are on each of the output studies held on with a brass nut.

[doubledoor]

where is that located? Also in stick mode when it squeals it sounds like it is the transformer. (coming from the back of the tunnel) and in V sense mode it sounds like the front igbt humming.

[cruizer]

open circuit voltage is somewhat too high. the bouncing between voltage and ocv is what its supposed to do. I wonder if the voltage pickup line has come off the back of the output stud/s

[doubledoor]

Yes I welded with it. Hooked it up to my xr alu machine and it welded smooth as can be. In the V sense mode it bounces between the volts you are set at and 96.8. It does not squeal like in stick mode but makes a humming noise. Not silent like the other modes.

[cruizer]

So you wire welded with it, or did you just put it in CV mode? Maybe put it in VS CV mode and see if the unit squeels.

[doubledoor]

So I have figured out that the decimal point on the volt display is burnt out. So in stick mode it is reading 98.9 volts and squealing. And 98.9 volts in scratch start tig mode. But runs fine in wire mode.

[cruizer]

Thank you for your time and advice so far. cruzier.

Well, I would pop a test board in, 99% sure it's the front display board though, obviously a programming glitch. And no it can't be reprogrammed, nor sent out and repaired.

[doubledoor]

Thank you for your time and advice so far. cruzier.

[doubledoor]

Don't really want to throw money at something if it won't fix it. What would you do at this point? I also noticed that in mig
mode the was no decimal point in the volt meter.

[cruizer]

So all the readings I have are good. The drain resistors are good. The diodes are good the gate is good. It's the front board that took out the diode and igbt?

No the output board likely got loose, Presto the igbts get hot and pop. The Front board does a lot of stuff and handles the programming. Not going to be repaired and would have to be replaced. The help 7 present is a little odd and is slightly confusing

[doubledoor]

Can the front board be repaired?