Bimax 132 welder broken wirefeeder

Not a great week. Yesterday I blew up two anglegrinders in a row and today I fried my welder. The wirefeeder is dead. The torch is fine, it reads 20.8 volts but when I measure the motor that controlls the wire feeder there's no voltage at all. I made a couple of pictures with some clarification here and there. Is there anyone that knows a thing or 2 about electrics or welders? It's a Bimax 123

This is the front of the welder


Rear of the welder


Better look of the pcb at the front of the welder

 

Hey Jagtech,

The trigger is fine. I opend up the MIG gun to see if anything obvious was broken there. The trigger is nothing more than a piece of plastic that pushes 2 strips of metal together. There's 20 volts across the 2 strips of metal and they connect just fine.

 

The voltage across the leads indeed drops to zero when the switch is pressed. The relay (translucent housing, 0301 written on it?) solder points look fine, no corossion or cracks, but when I press the switch, nothing noticable happens. No sounds, clicks or any mechanical movements inside.

 

I checked the relay (finder 40.61 0301). When the welder is turned on, 2 pins read 230V, just normal ac. The other side of the realy reads zero until is press the MIG gun switch, then it reads about 27V, slowly decreasing back to zero at a rate of about 0.1V every 0.5 seconds

 

Hey Jagtech,

I'll replace the relay. One other small problem: the relay is a finder 40.61 0301, but when I look for that particular relay, I find 40.61.xxx.0301 where xxx is a variety of numbers. Nowhere on the relay or the board is there any other information regarding the "xxx"
It's a 12v unit, which one should I buy?

 

Unfortunately there are no other numbers or identifiers on the relay. That said, is the relay I linked likely to be usefull?

 

Hey Jagtech

Not enough amps on that one. I already bought one earlier, a Finder 40.61.7.012.0300

*edit* and the forgot to mention it's not in stock, so now I get to wait 2 weeks. Marvelous.
Jagtech, the link you gave me is for a relay that has 10 amps - I need 16. Do you have other suggestions?

 

In the meantime I have a different problem. I disconnected a 4 prong rocker switch from a pressure washer pump to get the pump out of its housing. I made a picture of the wiring before doing so but the picture got deleted before I had a chance to upload it. Does anyone kow how to wire this thing back up?
The blue, white, light-green and green wire with the tabs attached need to go on the switch. Back and front of the switch are on the left.

 

Alright the relay FINALLY came in. I promptly solderd it to the board and turned on the welder, only to be greated by sparking right at the edge where the relay meets the pcb and partly inside the relay, between the most right pin and its opposing twin on the other side of this image. (image not the actual relay, but same pinout) I double-checked the solderjob and it's immaculate, indistinguishable from the other solders. What's going on here...

 

Hey Steve

The new relay is supposedly only different in that it isn't waterproof. The original is (probably, doesn't say the full part nr, because that would be silly!) a finder 40.61.7.012.0301, the new replacement is a 40.61.7.012.0300, where the zero at the end only indicate waterproofing. On further inspection, the new relay says 40.61s

If I take the old relay to an electrics shop, would they be able to give me a new, equally spec'd relay?

 

How would I test a shorted wirefeed motor? As for the sparks: if I turn on my welder again, the sparks happilly continue. the part where the short happens is hooked up to 230v I think, and the other half of the relay is "isolated" from the rest of the board since it doesn't close (haven't tried the trigger obviously)

 

Ok here are a couple of pictures

PCB and relay


Short point


Solder points


Where the wires lead