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Re: HV puncture of schedule 40 PVC
- To: tesla@xxxxxxxxxx
- Subject: Re: HV puncture of schedule 40 PVC
- From: "Tesla list" <tesla@xxxxxxxxxx>
- Date: Thu, 16 Dec 2004 19:59:36 -0700
- Delivered-to: testla@pupman.com
- Delivered-to: tesla@pupman.com
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- Resent-date: Thu, 16 Dec 2004 20:01:51 -0700 (MST)
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Original poster: "Antonio Carlos M. de Queiroz" <acmdq@xxxxxxxxxx>
Tesla list wrote:
>
> Original poster: "David Rieben" <drieben@xxxxxxxxxxxxxxx>
> My questions are does AC have a higher puncture
> coefficient than an equal DC voltage? Or is the white
> schedule 40 PVC pipe not near as puncture resistant
> as the grey schedule 80 electrical grade PVC, even
> though the wall thickness is about the same? Remem-
> ber, only half of the rated voltage was being felt at the
> PVC since the copper tube wand was grounded (mid-
> point grounded secondaries on the x -ray trannies -
> just like a huge NST). Any thoughts or comments
> are welcome.
A possible reason is that with AC there are corona currents
flowing to the surfaces of the PVC, heating it. With DC they
flow just to charge the capacitance across the PVC and stop.
Antonio Carlos M. de Queiroz