Powermax 900 not happy

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Howdy all, I have a Powermax 900 that I've had for a while and upgraded the torch, so far so good. But the cutting arc stopped turning on all I was getting was the pilot. So I thoroughly troubleshot it with the good folks at Hypertherm and they said it's probably the control board. So I sent it to a company that repairs pcb's and they said it had a couple of bad IC's and they fixed it. So all happy I put the board back in and .... same as before. And after a couple of tries now there's no pilot arc either anymore. I talked again to Hypertherm and they said it also could be the power pcb (041532). Or maybe the pilot control pcb (041486). Or maybe the IGBTs. And maybe I should just buy a new machine. The thing is I don't want to buy a new machine. And also this machine does not seem too complex, there has to be a way to find out what failed and fix it doggoneit! Does anyone have any suggestions? Are there ways to test the power pcb or the pilot control pcb? Any support would be much appreciated!Sent from my SM-N950U using Tapatalk
Reply:Hello I had mine do that and they told me it was not repairable get a new one. That was just there way of saying its older and no money for them. Fixed mine by checking the torch lead with a continuity check with a cheap meter and fond some dirty contacts in the head. It wouldn't beep when the meter was connected and I pulled the trigger hope yours is the same good luck!!
Reply:If yours has the screw on torch connector take a close look at all the connections. I found several with bad solder joint on both the torch side and the machine side. Resoldered them and fixed the problem.
Reply:Hmmm... I did check that and continuity seemed fine. I might try it again and measure from tip all the way into the machine just to be sure but I have a feeling I won't be that lucky....Sent from my SM-N950U using Tapatalk
Reply:Mine had continuity too, just wouldn't pass enough amps I guess, it's fairly easy to get in to see the machine side, IIRC. The torch side is only a couple screws.
Reply:Access is no problem right now I have the machine open. Which solder joints were bad and how did you determine they were bad? The ones to the screw connector? There are 6 white leads in the cable that go 3 each to 2 terminals on the screw connector. I measured them with an ohmmeter and they seemed fine. Is there a different test? The thing is that I don't even have a pilot arc which should be there if there some was continuity or am I getting this wrong?I certainly am no electronic wizard as you may have guessed...Sent from my SM-N950U using Tapatalk
Reply:Do you have a multimeter? If you do and post some pictures of the boards I can walk you through testing the IGBTs and some other tests. Does it show any signs of life like lights or fan running?My "collection":Homemade Stick WelderVictor O/A TorchAC 225Ideal Arc 250HF 90 Amp Flux CoreHF Mig 170Solar 2020 Plasma CutterPower i-Mig 140EHarris O/A torchHF Dual Mig 131140STAlpha Tig 200x
Reply:

Originally Posted by Iain P

Do you have a multimeter? If you do and post some pictures of the boards I can walk you through testing the IGBTs and some other tests. Does it show any signs of life like lights or fan running?
Reply:Have you checked the voltages they talk about on pages 3-20 and 3-22?My "collection":Homemade Stick WelderVictor O/A TorchAC 225Ideal Arc 250HF 90 Amp Flux CoreHF Mig 170Solar 2020 Plasma CutterPower i-Mig 140EHarris O/A torchHF Dual Mig 131140STAlpha Tig 200x
Reply:

Originally Posted by Iain P

Have you checked the voltages they talk about on pages 3-20 and 3-22?
Reply:

Originally Posted by Dragonblue24

Access is no problem right now I have the machine open. Which solder joints were bad and how did you determine they were bad? The ones to the screw connector? There are 6 white leads in the cable that go 3 each to 2 terminals on the screw connector. I measured them with an ohmmeter and they seemed fine. Is there a different test? The thing is that I don't even have a pilot arc which should be there if there some was continuity or am I getting this wrong?I certainly am no electronic wizard as you may have guessed...Sent from my SM-N950U using Tapatalk
Reply:

Originally Posted by Hobbytime

my dad use to fix electronics as a hobby a long time ago and many times just poking around with a plastic probe was enough to put back in place or have a component make contact again to have the unit( radio, computer or whatever he was fixing) come back to life and work again, all it takes is 1 little connection not making correct contact, also just because the ohm meter shows continuity doesnt mean it can carry the proper load for the unit to work..he would look at all the solder connections under magnification looking for any cracks in the solder joint or corrosion in the solder joint..