Miller 180sd weak arc

[69shoveled]

I have been trying to diagnose a Miller 180sd syncrowave welder I recently acquired. I tried searching all over the Internet and on this site.
The problem is a weak arc, and it's real irratic It won't get hot enough to melt the metal. It was taken to norco and they said they "think" it's the pc board.
I'm a welder and auto mechanic by trade but far from a welder repairman. I can have the board repaired in Florida by gem electronics for 290$ but I want to make sure it's the board. I have tried different leads pedals three phase, 220 all the same. I have had the board out and examined it closely and everything looks good. Ive cleaned and adjusted the spark gaps also. Any help would be great.

[duaneb55]

Could be the hall device that senses the weld output current. There have been many earlier 180 SD units that have exhibited similar characteristics caused by a faulty hall device.

I suggest contacting Miller Customer Service (920-734-9821) with the unit SN and description of how it's operating so they can walk you thru a diagnosis.

[cruizer]

Yep Hall / LEM is bad, merely get the part # off it and get another from Digikey...

[69shoveled]

I contacted Miller and they said unplug the hall sensor and see if it welds wide open. If it does I was unclear if it means it's not the switch or if it is? Thank you guys for the help. who is Digikey?

[H80N]

I contacted Miller and they said unplug the hall sensor and see if it welds wide open. If it does I was unclear if it means it's not the switch or if it is? Thank you guys for the help. who is Digikey?

digikey electronics

http://www.digikey.com/?WT.srch=1

[69shoveled]

Put a known good hall sensor in it same problem real irratic pulsing then it will try to tig but nowhere near hot enough- I unhooked hall sensor and it welded wide open burnt my tungsten off.

[cruizer]

well then your known good hall, either wasnt rated for this machine, or was no good to begin with. cant put any ole hall on it....

[69shoveled]

Was taken out of an identicle machine from work.

[69shoveled]

Shipped board out today to be repaired. Will update when I get it back.

[69shoveled]

Had board repaired still the same weak erratic arc. Could the Hall sensor and board been bad at the same time? Or they screwed me on the board repair?

[69shoveled]

Pulled board out of welder at work put it in my welder it worked. Inspected the board and resistor R77 was missing on mine. Gem electronics out of Davie Florida claims they repaired my board but they did not. Paid them 320$ do not send anything to these jokers.
I contacted Miller and they gave me the specs on the correct resistor. Have one on the way and in process of getting my money back. Will update when new resistor is installed.

[69shoveled]

[ryanjones2150]

so what did they do for your $320 besides ship the board back to you?

[69shoveled]

That's a really good question. Put pink marks on some of the chips & cleaned the board? Called them today told them board still don't work want a refund. Said that they would issue me a refund.
I don't know how you could miss a missing resistor if that's what you supposibly specialize in? Very aggravating.

[ryanjones2150]

no kidding. At least they're giving you your money back. Maybe they let one of the interns work on it or something.