Well, managed to lay down a couple of decent alloy welds, then this happened:
Anyone know what the bits are and if they are the expensive bits to have repaired?

Dead TIG2


Dead Tig1

[Edited on 6/4/13 by r1_pete]

what make if tig is it?

this service manual from esab shows the general circuitry
pdf
www.esab.com.ar/ar/sp/productos/upload/0740_800_172_mig_tig_3000i.pdf

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from your photos,, the lower circuit board will need replacing, and most probable the items on it too, - do any of the things on the heatsync have numbers on them?

looks an easy board to replace.

Hi, its a chinese one unfortunately, This One

Can't see any numbers on the components, I'll pop the heatsink brackets off and see if I can see any numbers.

That happened to mine and apparently it's caused by the heatsinks being too tight and cracking the trannies, they are all the same along that bank so have a look at the other and you should be able to replace it pretty easily from farnels or maplins etc, would also check the others too. You will need to take out the boards as there is another bank on the other side.

Hopefully the board itself isn't toast

Cheers

Rich

[Edited on 6/4/13 by RichardK]

The numbers on the Transistors is RJH3047 733 408, there are many RJH3047's in there, but with different suffixes, does the 733 & 408 actually mean anything??

You're probably right Richard, the first tranny is cracked.....

I'll work out the values ov the resistors and diods close by and rebuild the board, it doesn't look burned.

Then I'll reseat them all on the sinks a little looser with plenty of heat transfer grease.


Dead Tig 3

RJH3047 is a 300v Insulated Gate Bipolar Transistor (IGBT), originally made by Renesas but now discontinued. It's a fair bet those devices are Chinese copies however. The other numbers will most likely be date or batch codes.

It's unlikely you'll find an exact replacement from RS, Farnell or Digikey etc. but they do seem to be available from China through eBay: 10x RJH3047 IGBT RJH 3047 Transistor | eBay

[Edited on 6/4/13 by MikeRJ]

Thanks Mike, I've taken the card out, it looks repairable, so I've bought one of those 10 packs.

I've also mailed the manufacturer in China to see if I can get a replacement card..... I can hope

It looks like the Eastwood that Frost sells.

Hi mate, time difference got in the way!

I would also get some thermal compound and apply a very thin layer to the fronts and back when reassembling, available from eBay or any computer shop as its used on CPU coolers.

Hope you get it sorted!

Cheers

Rich