Miller xmt 350 VS good shape - $1100 - good deal or not?

[cruizer]

Can't see both the display and control board going out at the same time. What was the error code?

[cruizer]

The usual problem is with the output board, igbts, or SR1. The output board while expensive to buy, is really easy to fix. IGBT's are not particularly expensive.

[b.maker]

There are no error codes..I took it to a supposed certified Miller weld repair shop... they told me the 2 boards were bad. When I plug it in , everything appears to work. Just no output.
I have an IGBT tester and all of them checked out.? I also have a bench power supply and physically input power to the IGBT's and SR1 individually and everything checked out there as well. I also have a couple of capacitor checkers and both the big blue capacitors checked out as well. I tested the diodes and the resistors on the little board attached to the IGBT's(desoldering them) and all checked out. I checked the main switch for continuity and good contact along with loosening and cleaning and re-tightening any grounds or cables I could find...no dice. I just don't know enough to find the problem but I think I have the equipment(with the exception of an IC tester) to test and replace anything on the boards. I'm willing to try anything because it's just an "electronic spare parts for a robot" in its current state.

[cruizer]

No error codes makes it a blown zener on the display board. Display board runs the contactor circuit

[cruizer]

The control board usually gives a Help 6, the output board usually a help7, sometimes the control transformers to run the igbts blow which will also give you a help 7. But you blow a IGBT transformer, you also take out a igbt. Never the less, shoot me the serial# and I can pretty much tell you which Zener is blown.

[b.maker]

The board assembly numbers are 219820 D and 213664 . It also has LF-11 on it. The machines s/n is LF-121929 . Stock number is 903471. Huge thanks if I can get it working.

[cruizer]

Think its D15 or D21 on the display board. don't have to pull it out of the circuit to test it. Just use the diode test function on your meter.

Or you can just send the board to "Radwell" for repair.

[b.maker]

I already have the boards out and on a bench and I checked both D15 and D21 from the display board with the multimeter and there was voltage going both ways, approx 1.264v and 1.420v going one way and approx .567v and .595v the other. I desoldered both and both read .596v one way and the other way nothing. I have a Hakko 808, so desoldering isn't a problem. I also have an old oscilloscope. If you have another thing you want me to try I'm up for it.

[cruizer]

I'd be sending that board out for repair, tell them that the contactor circuit is fryed.

[b.maker]

The 2 places near me I've tried just want to replace the board. The 3 I tried online say it's unrepairable. I probably haven't found the right place yet. Thanks for you help though.