RE: PDT (Pig) failure modes

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

Original poster: "Dave Hartwick by way of Terry Fritz <twftesla-at-qwest-dot-net>" <ddhartwick-at-earthlink-dot-net>

David,
Yes, but what about the surviving the energy from a primary strike, for
example, which can be huge voltage wise? It is not hard to imagine the the
insulation used in the core not surviving such voltages. Minor charring may
be enough to start the failure ball rolling.

My safety gap was not grounded and the system took several primary
strikes---juicy ones at about 4 kVA from an 8" secondary. Dr. Resonance
seems to think this would be enough.

BTW, physically, my PDT does not appear to be very old at all. It looks just
like the ones generally in use now, festooning the telephone poles. But who
knows the actuall condition of the insulating material inside the core. The
dialectric properties of the paper, for example, could be shot, and still
physically appear to be normal.
Dave



Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Tesla729-at-cs-dot-com>

Ken, all,

I realize ANYTHING manmade will eventually wear out and ultimately
fail, but it seems to me that Dave's pig failed LONG before it should
have, due to aging! Pigs (PDTs-if you're politically correct:-) are de-
signed for the most rigorous electrical and environmental operation
and are designed to operate in these harsh environments for 20 to
30 years without a hitch. Occasionally there will be a "lemon", but
the vast majority of them are like a Timex watch - they'll take a lick-
in' and keep on tickin'. Like Terry says, our "coiling" doesn't really
even come close to challenging the BIL voltage design envelope of
these beast :-) They're designed to withstand direct lightning hits
(with the help of  lightning surge arresters) on their primary line
inputs and the kickbacks of Tesla coiling are quite puny in energy
compared to to lightning bolt-to-line hits ;-) BTW, lightning surge
arresters make good substitutes for safety gaps.

Coiling in Memphis,
David Rieben