Generator Core Iron Problem
Generator Core Iron Problem
(OP)
Hello,
We had an insulation failure on a hydro turbine generator. It was sent out for rewind and I am being told that the core iron is bad. They tested 3 times and still havve poor results. I am being told that the temperature is not stabilizing and this not uncommon for old generators with wavy iron. It is a 1905 generator.
1. What is meant by wavy iron?
2. I have a copy of the Stator Core Test sheet. Does anybody know of a primer or resource on what the tests are and how to interpet?
Thank you in advance for any and all replies.
We had an insulation failure on a hydro turbine generator. It was sent out for rewind and I am being told that the core iron is bad. They tested 3 times and still havve poor results. I am being told that the temperature is not stabilizing and this not uncommon for old generators with wavy iron. It is a 1905 generator.
1. What is meant by wavy iron?
2. I have a copy of the Stator Core Test sheet. Does anybody know of a primer or resource on what the tests are and how to interpet?
Thank you in advance for any and all replies.






RE: Generator Core Iron Problem
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RE: Generator Core Iron Problem
Unable to see your test sheet. In my opinion, that core is a centurion ready to be retired.
Those days they used hot-rolled magnetic sheets which had greater thickness variation than that of today's cold rolled sheets.
So, when you stack a core with a big bore, like hydro machines, you will see at the back of the core, the stacked core will appear wavy.
I would strongly recommend replacing the core with new cold rolled, non-grain oriented sheets, which have significantly lower losses.
* Women are like the police. They can have all the evidence in the world and yet they still want a confession - Chris Rock *
RE: Generator Core Iron Problem
I didn't have the luxury of handling century-old electrical equipment but a parallel experience looks the same as your present problem! I have the same problem with a motor that exhibited higher than normal no-load current drawn. We analyzed the problem and came to a conclusion that the culprit is the core of the stator. We had that motor core re-stacked and the problem was gone.
hope this helps.