Welder problem

[landrover598]

Any grown ups know about how welders work who could help me ?

I was hapily welding away making a new rear crossmember when my MIG (SIP 145) stopped arcing, the wire is feeding but it won't strike an arc, only a very small sparkling when the wire is fed across the steel.

Any suggestion of how to fix it, before i start window shoping for a new unit

[steve b]

Hi

I may be stating the obvious but have you checked the earth cable connection to clamp and inside the welder case?

Also worth taking the torch apart and checking the weld current connection, same in the case too. Is it a euro torch ?

...unplugged from mains

cheers

Steveb

[landrover598]

Yes, i've checked all the earth cable connections, innside the set, at the clamp and at the extension join in the middle of the cable. All OK.

It's not a euro torch, but if i can't fix it, it'll be a good excuse to upgrade to one with a euro torch.

[LandyLee]

noticed you are not too far away !! I have a clarke 150 TE you can borrow until you get yours sorted , its sitting in the attic unused . As for you`re welder , it could be break in wire to torch or transformer problem etc etc .

[secondjeremy]

Also worth checking the mains plug and any extension lead - and trying it in another socket - preferably elsewhere.(I blew part of my house wiring with my welder which was a little less powerful than yours.)

Take the plug to pieces and look for burning etc.

[LandyManLuke]

Is the contactor pulling in? Look for an AC voltage across the primary and secondary windings on the transformer, and a DC voltage (well almost!) across the output diodes.

[Highway_Star]

Most SIPs don't have contactors, not gas solenoids, it's all done in the trigger.

First check the DC feed wire hasn't come adrift near the wire feeder assembly, they love to do that.

Second check the DC feed wire hasn't come adrift inside the torch, they also love to do that.

If it's the feed wire, you can get suitably heavy cable in the boy racer section at Halfords, as well as appropriate sized lugs etc, I know this 'cos my old SIP did this to me one summer evening, and Halfords was the only place open.

Beyond that, you could be looking at a relay problem on the PCB, they love to burn those up, or possibly a diode gone in the rectifier section, eliminate the easy faults before looking at the diodes. They are easy enough to test and replace, but you won't see anything visibly wrong.]

I guess an even more unlikely fault is burnt out windings in the transformer. That realistically is new welder time.

Have a read on MIG welding forum too.

[landrover598]

First check the DC feed wire hasn't come adrift near the wire feeder assembly, they love to do that.

After much checking over of wires, and then checking them again, i removed, cleaned and re-crimped this connection and it's working now

Cheers.