millermatic 130 problem

[evilleshepherd]

Hi all, I'm new here to weldingweb so I hope I get this right. I own an older millermatic 130 that I got in a trade for some work done. It used to work great! Now when I pull the trigger the ice cube relay picks up but not the larger relay/contactor. With the trigger pulled and icecube relay picked up I can push in the plunger on the larger contactor and it will pick up and stay in, running the wire feed motor. I can then let off the trigger and press it again and the welder will feed wire like it should, but this is only if I pull the trigger within 5-6 seconds of letting it off. If I wait to around 10 seconds or longer I will have to manually push the plunger in again. I have removed the larger contactor and applied 24VAC and it operates every time. The gun/liner is fairly new and worked fine so I don't think it is part of the problem. The larger contactor works everytime I apply 24vac so I don't think it is the problem either. I have also checked for loose connections and found none. I can't check the small circuit board beyond looking for burnt components and I'm afraid if this is the problem it won't be worth fixing. Anybody have any ideas?

[lamename]

Start at the contactor coil and work back w meter.

[ccawgc]

Look at your diagram on the inside of the cover. make sure you have 24vac to the pcb.
Then put your meter from G to K Should get 24vac. It should go to zero when the trigger is pulled. This is looking at the contacts of the little relay on the pcb. If it closes every time, but has a large voltage drop, the contacts are worn out. A new relay is a lot cheaper that the whole pcb. @ $188 list. Also measure the 24vac supply and make sure it stays up around 24 volts. This would be a bad connection or Fan transformer motor.
Get help, if you do not know how to use a voltmeter safely.

This should be moved to the miller room.

[evilleshepherd]

Thanks guys, I'll start looking where you suggested. I had checked the small relay on the PCB to see that it was closing (continuity check) and it was, but did not look for volltage drop. Thanks again!

[evilleshepherd]

Thanks ccawgc, I didn't realize there was a 'Miller Room" but have now that I've found it I will post there, thanks again!

[evilleshepherd]

ok guys, again I'm new here and not finding my way around the site too well. How does one find "The Miller Room"? Is it a designated area for only Miller questions or do I just search for 'Miller' ? Is there a list of all the designated areas somewhere? Any help is appreciated, thanks!

[davido30093]

http://weldingweb.com/forumdisplay.php?f=16

[farmer37]

If you dont under stand how somthing works you cant repair it.The miller 130 cost 600 bucks new so its worth fixing.Take it to a welding shop that has a service man.My 130 is a nice welder, much better than some of the HF stuff.

[evilleshepherd]

I understand what the old 130 cost new, I just priced a brand new Miller 180 220V unit at $750 and a 110V unit at around $625. But, what I meant by possibly "not worth fixing" is that a service shop repair could easily be around $200 or more and I'd rather put that kind of cash into a brand new welder instaed of a 15 - 20 yr. old wleder that may have the next major part fail next month. By the time I replace a circuit board, a drive motor and gun/cable I have spent as much as a brand new welder. I have taken it to a local miller repair shop at a minimum cost of $60.00/hr just to tell me what is wrong with it. I was told that the circuit boards can cost any where from $100 - $300 depending on which board I have, plus the labor on top of that. If they tell me it is the board I will try CCAWGC's advice and replace the small board relay. Thanks for the advice guys!

[fowlwaters]

If it is the board check out York eletronics my mother board went out on my MM210 and sent the board to York and they have a fast turn around and only cost $150. Welding repair shop want $600+ to fix it.