Transformer help needed

Well I've traced what I think is a fault on my genny to an open circuit 3 phase transformer. It's delta wired with quite thin primary
and thicker secondary. All 3 primary windings show open circuit with my multimeter. I've spend most of the afternoon whistling Old MacDonald's Farm to myself as I stripped out the laminations removing E's and I's interspersed with frequent oh's. I now have a pile of said E's and I's and some wire on order to try rewinding the coils. Fortunately the primaryís are on the outside. Inevitably, 3 or 4 Eís broke during dismantling. Iím working on the basis that 3 out of 120 arenít significant and I will probably have trouble getting them all back in anyway. The transformerís on the excitation circuit BTW. Is there anything I should be aware of or should I give up now? Would a rewind company do a much better job on a purpose made machine? If so, is it worth just paying them to do it for me?
Thanks in advance
John
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"John" wrote
Well I've traced what I think is a fault on my genny to an open circuit 3 phase transformer. It's delta wired with quite thin primary and thicker secondary. All 3 primary windings show open circuit with my multimeter. I've spend most of the afternoon whistling Old MacDonald's Farm to myself as I stripped out the laminations removing E's and I's interspersed with frequent oh's. I now have a pile of said E's and I's and some wire on order to try rewinding the coils. Fortunately the primaryís are on the outside. Inevitably, 3 or 4 Eís broke during dismantling. Iím working on the basis that 3 out of 120 arenít significant and I will probably have trouble getting them all back in anyway. The transformerís on the excitation circuit BTW. Is there anything I should be aware of or should I give up now? Would a rewind company do a much better job on a purpose made machine? If so, is it worth just paying them to do it for me?
I'd recommend taking it to a rewind shop. You'll be extremely lucky if you can wind as neatly as if it were done on a coil winder, which means that you won't be able to fit the correct number of turns on the bobbin.
Above all, don't remove the failed windings - the rewind shop will need to know the number of turns to perform the rewind.
If you have a specification for the transformer, you could think about getting a new one made. They aren't that expensive.
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wrote:

Give me some accurate dimensions and I'll see if any of our standard lam's wll fit. Also need the thickness. 0.050" are standard 800/50 or 400/50 grade, there are also higher-spec/thinner lams and GO (Grain Orientated) types.
Peter -- Peter A Forbes Prepair Ltd, Rushden, UK snipped-for-privacy@prepair.co.uk http://www.prepair.co.uk http://www.prepair.eu
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Thanks John and Peter for your help. Unfortunately I don't have any details about the alternator, let alone the excitation transformers I spoke a rewind company and their price made me sit down. I'm now looking at other ways around it. Thanks again.
John
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