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>

Mark,
What a beautiful strike! No safety gap-- and no strike rail, I assume

This PDT (pole distribution transformer) must have been compromised when I
received it. Something I've not mentioned to the group is the fact that I've
not put much time on at all.
Maybe 30-60 minutes total coil run time. Max streamer length has been 50".

Further analysis of the failure may take place in conjunction with some fine
list minds like Terry F and Steve Mach. I may send the core to Terry, if I
can muster the courage for the job.
I'm psychologically impaired right now, having difficulty making an MOT
supply  work without transformer arcing.

Dave



Original poster: "Mark W. Stolz by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<mark_w_stolz-at-hotmail-dot-com>

Dave,

A primary strike is probably not going to hurt your pig.  Here's a shot of a
nice solid primary hit running ~12kVA.  The coil is a 12", the tank that
night was around .187uF.
http://users2.ev1-dot-net/~nmyreality/tesla/AJ010803/primary_strike.jpg

And no safety gap at all.  This is just one of many strikes I've seen this
coil take.

Mark Stolz
Houston, TX


>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