WestingHouse 15kv VCP-W Switchgear 2

[AfricanAmber9]

We are doing maintenance on our VCP breakers and have heard some extra 'sizzling', more than normal when racking out breakers. We then opened the shutters with the breaker out of the cell, turned off the lights and were able to see partial discharge occurring on the line side of the stabs. There is a a metal cover over the Poly barrier that fit over the metal stabs individually.

I hope the picture populates for reference. The metal is super thin and the only reason I would think for this assembly would be for the mounting bolts that hold the Poly barrier in place, and when you torque down on them it won't crush the poly barrier. Anyhow, the discharge is happening on the the small tabs and am wondering if anyone has come across this issue. I am sure over time we will incur more of an issue with breakdown and tracking. I appreciate your time.

 

[xnuke]

Contact Eaton, as they own the VCP line now.

xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[jraef]

Every time (twice) I have opened live MV gear and turned off the lights, I’ve seen (from a respectful distance) partial discharge happening. One time it was really eerie looking, like living spider webs crawling along surface of the conductors, following traces of dust. Wish I had taken a video of it.


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[AfricanAmber9]

Thank you. I did get a response back from Eaton, initially their response was a partial discharge from the the mounting bolts, which I argued it wasn't and then the next day they said I need a new 'corona' ring, and at least one tab should make contact with the vertical bus to mitigate any partial discharge. I don't think that is the case because I see it happening throughout this Main Bus, with one of the tabs touching. Maybe if the Corona ring had been filed from any sharp edges, including the 4 'Tangs' there would be no partial discharge. Thanks for your response!