Ifa 185 smart mig

[Garyj88]

Hi guys,

I'm new to the forum I was hoping for some help

I recently got an ifa smart mig 185 off a friend which wasn't working I had a fan running but not power to wire feed

I stripped it down and tested the relay (finder 65.31) which wasn't working. I ordered a new relay and the put it in but the relay is opening and closing continuously and extremely fast.

Eventually it overheated and fried

Has anyone got any suggestions or questions I really don't like throwing things out that have a chance

 

[rtbcomp]

Welcome to the forum.

Really need the circuit for this one. It sounds like the relay is being powered through its own contacts and acting like a buzzer. It could also mean a rectifier has shorted and the relay is being fed with AC instead of DC.

 

[Garyj88]

would it be hepful if i attached a picture of the circuit board....

I disconnected the circuit board completely and the relay still buzzes..

i disconnected the motor and it still buzzes

this must be a odd ball machine as i can never find any details about it... i presumme it is a sip of some sort?

 

[rtbcomp]

Some photos of the PCB and more general shots of the outside & inside would help, it may be another make re-badged.

If you could point out the offending relay that would help too.

 

[Garyj88]

ok i will take pics tonight....

 

[scotty41]

I have had that buzzing with a relay when I fitted an incorrect one, cant quite remember but it was a SPDT, twin. rs part number matched to it, but it was not the right one.
SPDT PCB relay, 5mm pin, 16A 48Vdc rs stock no 680-3741

fitted exactly but the version on my welder was a Double SPDT (Single pole double throw double) didn't know they existed.
I only found out by taking the old one apart and the new one and seeing how they latched inside.
just a though.

 

[Garyj88]

this is the pics of the welder and circuit board plus the other bits inside the welder

 

[Garyj88]

relay that is bizzing at the bottom sounds like it is clicking on and off constantly

 

[rtbcomp]

I would say that is a re-badged SIP TopMig.

I take it the new relay is identical to the old one?

It looks like it has had a Eurotorch conversion fitted to it, do you think this relay may be part of that and the fault lies with the conversion itself?

Where is the relay actually located?

Did the relay start buzzing when you applied power or when you pulled the trigger?

 

[Garyj88]

The welder was working ok when my friend bought it he used it for a few months then it stopped working he just bought a new one! This is wat made me think the conversion was done correctly

the relay was the exact same replacement.

It buzzes as soon as I turn welder on and feeds wire constantly!

I unplugged circuit board completely but still buzzes

 

[rtbcomp]

Does it try to feed wire with the torch disconnected?

 

[Garyj88]

Yes it does

 

[rtbcomp]

Can you hear a distinctive "clunk" when you switch on?

Does the wire feed with the relay disconnected?

 

[Garyj88]

I can hear a clunk yes when it start. When I put new relay in the other night I turned wire feed up it was constantly coming out of gun. I turned it down and put earth clamp on metal and managed to get it to weld al be it was quite weak! I cranked up the amps and the relay overheated and blew up!

Baring in mind the relay contstantly clicked the whole time in this process

 

[Garyj88]

This is the relay the two black wires go to the circuit board.

 

[Garyj88]

The blue wire goes to the on.off switch and the other wire goes to whatever the part in the second picture

 

[rtbcomp]

I'm beginning to wonder if you've got a faulty rectifier.

If you disconnect the rectifier unit completely and do a resistance check on each diode in turn (both directions). The should have a low resistance in one direction and a high one in the other.

 

[Garyj88]

This is the rectifier. I take it I have to check the two blue diodes! Do I need to remove them from the rectifier or test them on it. The two diodes are joined.

Is there a best setting on the multimeter to use its a sealey mm20

Thanks for ur help

 

[Garyj88]

I get .465 when I test diodes. When I reverse it I get 0. Do I have to test the yellow part?

 

[rtbcomp]

Those blue things arent diodes, they're suppressors of some sort. Those 6 buttons look more like diodes, but I would expect to find 4 or 2, not sure why 6.

Most multimeters have a diode test position on the ohms range, it's most likely indicated by the diode symbol, an arrow with a line across the pointy end.