No announcement yet.

Xmt 350

  • Filter
  • Time
  • Show
Clear All
new posts

  • Xmt 350

    Trying to repair a welder XMT 350 Serial LH. I would like to repair the boards if feasible. I have done all the pre-power checks from the red-d-arc service manual. I've only included the tests that didn't pass. Appreciate any insight as to what happened with this welder and the steps needed to repair it. Thanks for your help.

  • #2
    Those modules are getting hard to find and/or very expensive. First step is seeing if you can get them.


    • #3
      I retested the failed test points in section 6-5 with r14 shorted and they passed. Leading me to believe the mod1 is fine.


      • #4
        Originally posted by Bushytails View Post
        Those modules are getting hard to find and/or very expensive. First step is seeing if you can get them.
        Are these new ones that much different internally than the older ones?

        Click image for larger version

Name:	Screenshot_20210429-011204_Chrome.jpg
Views:	103
Size:	861.8 KB
ID:	614768
        Dynasty 400 Wireless
        Coolmate 3.5
        Aerowave loaded with Sequencer and pulse
        ​Watermate 1A
        XMT350 CC/CV
        S74DX Feeder
        Optima Pulse Pendant
        30A spoolgun
        Neverlast 100 amp plasma with Hyper Duramax torch
        Avortec 280 mig
        GO CNC Poweredge CC/CV pulse and double pulse
        Harris Old school 2 stage Oxy/Ace
        Victor flow meters
        Flametech Duel flowmeter
        Just a hilljack in the woods with fancy welding equipment
        and a pet Raccoon.


        • #5
          Not sure how different they are. Might be able to look at the parts diagram. For the PC1 I have a new R14 resistor, still need the R8 resistor. The R8 costs $57.32 from Miller part 246-069. It's custom made for Miller by Caddock Electronics Part MS315-39K-1%.

          The PC1 board costs $1182 from Miller. Not sure of the extent of the damage to the rest of the machine.


          • #6
            Here's the parts diagram for this machine.


            • #7
              Sorry for the very late post on this. Have you made any progress? If one of your bleeder resistors failed, there's a very good chance your capacitors are gone as well. You will need to replace both capacitors. It's worth replacing both bleed resistors (are they the new orange ones) and a must to replace both capacitors. There is a guy on eBay selling the caps for cheap, but he doesn't know or care what they go to - search the capacitor part number on eBay.

              Your PC1 needs at least a new module - that buck driver is in the Semikron SK10GHR123ii module sitting below the large heatsink. It's spendy - there's a guy in Texas who can get them for ~$150. How far further have you gone through the pre-power checks?


              • #8
                I will see if I can get and work through a PC1 repair. If you see my Dynasty 200 Low Buss Voltage thread, you can get an idea on how to run down the auxiliary power issues. The XMT 350 is similar, but uses a full bridge inverter through a large transformer instead of the flyback converter to power the rest of the board.