Announcement

Collapse
No announcement yet.

Shopmaster blows breaker MIG only

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    Right, the wirefeeder is unplugged. It should not feed.

    Comment


    • #17
      So now we have determined the problem is NOT with the power source, its with the feeder.

      What kind of feeder? model and serial#

      Comment


      • #18
        S22A Wire feeder, s/n KD413282

        Comment


        • #19
          Shorting a & b turns on the contactor in the machine, just as you hit the trigger on your gun. You either have a problem with the control cord, extremely likely, or a board problem. Never the less, its NOT the shopmaster. Might want to meter the amphenol on the master, A to G must be around 24VAC. The 22a uses only 3 wires a,b,g, You may have other wires in there causing problems.

          Comment


          • #20
            I will be back to this, but probably no time until the weekend.
            Thanks for all the help, I'll report what I find.

            Steve

            Comment


            • #21
              Things change

              The welder stopped throwing the breaker.

              While I had it open, I cleaned up the inside of the wire feeder, thinking that an intermittent problem might be leakage. No compressed air was used.

              I fed the wire with the trigger on the gun to fill the hose. It was almost to the gun when it quit feeding. If I use the jog button, the wire feeds with no problem. When I use the trigger on the gun, I can hear the gas solenoid activate, so the trigger is working. Wire feed does not work with trigger, does work with jog.

              I've been working on understanding the schematic. It seems incomplete; I can follow the trigger wire only up to a point and then the schematic loses it.

              Steve

              Comment


              • #22
                Things stay the same

                Cancel that last post. What happened was the preflow knob got moved to several seconds while I was cleaning up. This was long enough that I didn't think the trigger was making it feed. With preflow on minimum, the wire feed works like normal.

                While I was trying this out, the breaker popped once more. Reset it and did some welding, no additional problems.

                So I'm back to where I started, intermittently blowing the breaker.

                When I jumpered A+B on the connector, I didn't hear anything like a contactor connection. Is this right? I know the gas solenoid isn't going to switch, but it seems like there should still be a contactor go off in the main box.

                Steve

                Comment


                • #23
                  sajurcaju,


                  Question for you?

                  What is your input voltage you are using with the 50 amp breaker? One thought I had with reviewing your thread here was if the breaker is undersized and your running this on a lower voltage the in-rush current over time will weaken the breaker. The in-rush is caused by charging the cap bank in the CV mode. The current required to do this is much higher than you may think for the sort period of time.

                  Make sure your breaker is properly sized for the input voltage you are putting into it.

                  Let us know how that works for you.

                  Lemo

                  Comment


                  • #24
                    Lemo, we already figured that he had a low breaker, however, triggering his gun blew the breaker imediately, jumpering "A" and "B" did not. Really no difference if his feeder was ok. I believe the problem is with his control cable to his feeder.

                    Comment


                    • #25
                      Lemo, I'm running on 240V single phase. Good point about inrush, I hadn't thought of that. I'll look for a larger breaker. I have tried it on a different 50A circuit with the same results. The breaker box was a new install 3 years ago, for what it's worth.

                      Cruizer, I really appreciate the detail you've helped me with here. On the control cable, what am I looking for? I'm having a hard time picturing what could go wrong in a control line that would pop the breaker.

                      It shouldn't be a big deal to just replace the control line, end to end, but I like to get to the bottom of these things. I should probably start with the short end attached to the wire feeder.

                      Thanks,
                      Steve

                      Comment


                      • #26
                        Like I mentioned crossing A & B on the machine does the same thing as hitting the trigger on the gun. Soooooo, hitting the trigger hits the breaker, crossing a & b does nothing. This makes the problem with the feeder and cable. Now all the feeder is using is a,b,g. Test em

                        Comment


                        • #27
                          This is an intermittent problem. I did some welding last weekend, making a bracket. Some days are better than others.

                          When I was shorting A+B, I checked the pins with my meter. All were ok then (didn't blow the breaker either).

                          What I was asking is how the signal wires would flip the breaker. Am I looking for a short to ground? It seems like the machine would have something smaller than a 50A breaker protecting signal wires.

                          Steve

                          Comment


                          • #28
                            Yes there is protection provided A & G were wired correctly, however if they are wired in reverse, you'd have no protection, but the unit would still work. It all connects to the primary transformer. And thats where I think the problem is. (control cable)

                            This surge also wears out the breaker.

                            I see it all the time from either factory made cables or from half wit cable building techs.

                            Comment


                            • #29
                              Cruiser,

                              With 240 volt power on this unit it is required to have a 100 amp input breaker. Now I realize that he probably is not using the machine to its full rated output but I believe the intermittent issue is caused by the undersized breaker. I personally have the same machine and feeder running .035 solid wire in my own shop. Early on I had a similar issue with tripping the breaker in CV mode as I only had a 50 amp installed and it did the same thing. I had to increase the breaker size to 60 amps to eliminate my problem. The 50 amp worked for a while but over time it started doing exactly as he described.

                              I know with a 60 amp I am still undersized from what is recommended but it has not been a problem any more. I did this at least 10 years ago.

                              Sajurcaju you will have to verify your input box and system will handle a larger breaker.

                              Regards,

                              Lemo

                              Comment


                              • #30
                                The breaker was easy to try, so I put in an 80A breaker. I couldn't even turn on the main switch on the welder without popping it. Tried it with the other circuit (50A), same result, can't blame the breaker. The welder was set to 29V and the wire feeder to 400 ipm.

                                Back to being plugged into the new 80A breaker. If I set the welder to 29V and the wire feed to 300 ipm, I can turn on the main switch and the fan runs. If I change the wire feed to 400 ipm and then try to turn on the main switch, breaker blows every time. So it sure looks like something in the wire feed.

                                I'll measure the pins in the Amphenol connector and see if they match up to the documentation, especially a possible swap between A and G. Additional advice will be greatly appreciated.

                                Steve
                                Last edited by sajurcaju; 12-14-2013, 12:10 PM.

                                Comment

                                Working...
                                X