Re: Tubing for high voltage wire

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Crow Leader by way of Terry Fritz <teslalist-at-qwest-dot-net>" <tesla-at-lists.symmetric-dot-net>

May I ask what the insulation was made of in the underwater test?

KEN
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, January 01, 2003 6:17 PM
Subject: Re: Tubing for high voltage wire


 > Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>"
<jimlux-at-earthlink-dot-net>
 >
 >
 > ----- > <SNIP>
 >  >  >
 >  >  >Also, are there any readily available kinds of tubing that have a
high
 >  >  >dielectric rating to make HV wire with?  I haven't found a listing
for
 >  >  >clear vinyl tubing's puncture voltage yet. If anyone knows this
please
 >  >  >tell me.
 >  >  >
 >  >
 >  > I don't have any specs, but I can tell you from personal experience
that
 >  > the clear tubing used with oxygen masks in hospitals withstands my 14.4
 >  > KV pig power with no punctures!  Make friends with a nurse or doctor
and
 >  > you'll have a ready supply, as they are only used once then tossed out.
 >  > I use teflon insulated # 16 wire pulled through the tubing for all of
 >  > my high voltage leads, save for the high current ones in the primary.
 >  >
 > Interesting.. so, you actually have two layers of insulation. The first
 > being teflon (generically, PTFE) in close contact with the conductor which
 > is roughly 0.05 inches in diameter.
 >
 > How do you know there are no punctures?  I've been involved in testing a
 > variety of insulated wire for 18-20 kV over the past year, and it's pretty
 > subtle when it starts to fail. For example, a piece of 30 kV rated wire
was
 > immersed in a conductive liquid (impure water) and run at 20 kV DC for a
 > number of hours.  We watched for two things: 1) partial discharge and 2)
 > increase in leakage current, both of which inevitably occurred after 36-48
 > hours or so.  We also did tests with the wire laying on a metal plate.  In
 > all these, you couldn't see the pinholes developing, although in an
 > egregious case, you could see the corona in the dark.
 >
 >
 >