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boxer3maine
07-16-2011, 09:03 AM
I had done this with a subaru loyale.. found a resistor burned. if it burned once in the ecu it will do it again. I gave it a big one... went hot rod on me.(true story) it may have been "half connected" the whole time.

identifying parts is not easy. mosfet from transistor etc..
I was reading up on my mig welder and learned transformers could possibly last hundreds of years.. just huge windings like on a telephone pole but small for welding. 120 volt to 30, wind up the amps to melt the wire. I find the 30v is a hoax, most go to 12. they are built for international, maybe they got other powers as that derivitive of final 30.

anyway, as common sense dictates:
http://lh5.ggpht.com/-r_TKFzoUr74/Th8m4N1V55I/AAAAAAAACMU/9AGcoCzq7SU/welderfix%252520005w1_thumb%25255B1%25255D.jpg?img max=800 (http://lh5.ggpht.com/-FD5UnQW-Ny4/Th8m1S6oDSI/AAAAAAAACMM/CgYc4jha8I8/s1600-h/welderfix%252520005w1%25255B3%25255D.jpg)


I could not id some of the parts. I found a diode, resistors, trnsistor and tested them.all good. volts in, no out.. this means something somehwre on this dainty ass midget world pcb is flunked.

one thing that did not bridge was the rectifier. a tiny piece. (http://www.westfloridacomponents.com/DI077/0.8A+800mA+600V+Bridge+Rectifier+B250C800.html)
I want to go for this as a repair.

before I attempt this... is there a chance a bigger one can get put in? .8amp is the culprit. I sneeze with more air force veteran static than that. I found bigger running on the same 12v..could it take it?

any help appreciated. These migs are turning out to be a nerds heaven. The pcb is leaving new machines dead. To go as far as my own did.. well, it means it has a stable transformer. Worth a fix.

..or if you know anyone that enjoys fixing these. the board is so small it can be put into a air bagged envelope.

abnormal
07-16-2011, 09:50 AM
A higher current rated one will work fine, just make sure the lead out is matched to the one that's in there (~+~-). Make sure the voltage rating is equal or greater as well. See the 1.5A one on top of the page - link below.

If there's room you could install a high current different packaged one, (like the 6A ones in the link below). Some fancy lead bending / insulating would be required to match the pcb's lead out.

http://www.goldmine-elec-products.com/products.asp?dept=1133

hth

boxer3maine
07-16-2011, 10:10 AM
hey thanks...

I did find a whole list of different things to do.

I fouund something on the board that kicked off the volt meter... no power on the board. :eek:

I may have a little nuker.

checking the little rectifier showed a quick blip in continuity instead of a diode bridge in a circle.. that may be another fail.

the stuck gadget is quite something.
if interested wiull get photo..

as of this moment I am off to get another welding machine (currently driving car with broken rear end) :lol:

they shoulda kept everything like b-rally days :up: