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Congratulations waross on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!
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Poloraziation Index
To electricpete Yes I go to LEMUG, are you going in August? I think we are dancing around the whole PI issue here. Hypress was looking for a good PI acceptance number for a new, unused motor. The ones he tested seemed to be high. Moisture seemed to be a possibility, especially for a modern...- jb17136
- Post #20
- Forum: Electric motors & generators engineering
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Poloraziation Index
To Electricpete. I would agree that suspecting moisture due to a high PI for a modern winding would be a departure except the initial conditions were: new motors, never in service. I assumed storage of some kind, and while dirt, contamination, and deterioration and other normal enemies of...- jb17136
- Post #16
- Forum: Electric motors & generators engineering
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Poloraziation Index
I agree with utvol, the PdMA tester is a good tool. My first question would be what is the resistance to ground and how quickly does it get there. If the resistance to ground exceeds 5 gigohms in the first minute and stays there througought the 10 minute test with a good smooth curve, then the...- jb17136
- Post #10
- Forum: Electric motors & generators engineering
