TurbineGen
Electrical
- Mar 1, 2007
- 489
We are having issues with high PD levels in one of our generators. The generator was just rewound last year. It is a 13.5 kV machine. The machine has been tested while in service twice and both times the readings were nearly the same.
We have crawled through the unit several times and find no evidence of excessive PD. In crawling through, we noticed the coaxial cable from one of the couplers is in contact with the bus ring. We are guessing that the coaxial cable from the coupler which is in contact with the bus ring could be giving a false reading. Could that be causing a false reading? If so, what clearance should there be between the cable and the bus rings? Any other thoughts/suggestions on what we should be looking for?
We have crawled through the unit several times and find no evidence of excessive PD. In crawling through, we noticed the coaxial cable from one of the couplers is in contact with the bus ring. We are guessing that the coaxial cable from the coupler which is in contact with the bus ring could be giving a false reading. Could that be causing a false reading? If so, what clearance should there be between the cable and the bus rings? Any other thoughts/suggestions on what we should be looking for?