Re: PDT (Pig) failure modes (fwd)

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

Original poster: "John Richardson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jprich-at-up-dot-net>


Hi guys,

In response to the threads below:  I really don't know a whole bunch about
electronics, or some of the stuff that crosses this list.  (Recurred
childhood interest, so please stick with me.)  It would seem to me that in
order to get that amount of H20 in the trans oil, enough that would
precipitate failure, there would have to have been a huge failure in the
sealing system, something that would have been large enough to be glaringly
obvious enough to have been visible to  someone doing a quick visible check
of  your PDT before shipment.  Secondly,  it would seem to me that even a
minute amount of water in the bottom of the PT case wouldn't present a huge
problem, as I'm assuming that the internals are a measure of distance above
the container bottom, and oil floats on H20.(?!)  In my experience with
electricity, and the vast majority of it is real world everyday stuff  vs.
what we deal with on the list,  I don't understand how this would be a
problem.  Help a high frequency virgin understand this, please.

Thanks, and sorry for the length.

John Richardson

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-poodle.pupman-dot-com.rmpg-dot-org>
Sent: Thursday, September 19, 2002 7:36 PM
Subject: Re: PDT (Pig) failure modes (fwd)


> Original poster: Tesla List Moderator <mod1-at-poodle.pupman-dot-com>
>
>
>
> ---------- Forwarded message ----------
> Date: Wed, 18 Sep 2002 21:37:33 -0500
> From: Crow Leader <tesla-at-lists.symmetric-dot-net>
> To: Tesla list <tesla-at-pupman-dot-com>
> Subject: Re: PDT (Pig) failure modes
>
> It does not sound like a water filled transformer supplier is reliable. I
> tried to order from them before and the best answer as to age and
condition
> was "some look new".
>
>
> KEN
> ----- Original Message -----
> From: "Tesla list" <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Wednesday, September 18, 2002 8:59 PM
> Subject: Re: PDT (Pig) failure modes
>
>
> > Original poster: "Steve White by way of Terry Fritz
<twftesla-at-qwest-dot-net>"
> <slwhite-at-zeus.ia-dot-net>
> >
> > Just a note of caution. Since T&R again seems to be willing to sell pigs
> for
> > Tesla coil use, let us be careful not to antagonize them by asking for
> > replacements, etc.. Even though the transformer may have indeed been
> > defective, I think it would be wiser just to eat one every now and then
> than
> > to beat up on them because one of their tranformers failed under Tesla
> coil
> > duty. I bought mine from T&R about a year ago and I want to keep them as
a
> > reliable supplier.
> >
> > Steve: Coiling in Iowa
> >
> > ----- Original Message -----
> > From: "Tesla list" <tesla-at-pupman-dot-com>
> > To: <tesla-at-pupman-dot-com>
> > Sent: Tuesday, September 17, 2002 11:30 AM
> > Subject: RE: PDT (Pig) failure modes
> >
> >
> > > Original poster: "Dave Hartwick by way of Terry Fritz
> > <twftesla-at-qwest-dot-net>" <ddhartwick-at-earthlink-dot-net>
> > >
> > > Godfrey,
> > > Very interesting. I never considered thermal expansion as a factor.
> > >
> > > It is clear that repair is virtually impossible unless rewinding is
> > > persued--forget it. By the time I do that, I may as well obtain
> > laminations
> > > and build a xfmr from scratch that is specifically designed for Tesla
> > duty.
> > > One feature of such a xfmr would be easily removable windings and a
> > variable
> > > magnetic shunt.
> > >
> > > I'm SURE Tesla duty would not be considered normal by T&R! I did talk
to
> > > them yesterday and they are not willing to replace the core, which is
> > > expected. They are willing to sell me a complete replacement unit, no
> > > questions asked concerning usage. Good enough for me, though I might
buy
> > one
> > > from Dr. Resonance. I think there is some water floating around in the
> > > bottom of the tank of this dead PDT, also some rusty chunks of
> something.
> > I
> > > must think that I received the unit from T&R in this condition since
> it's
> > > just been sitting in my basement, well protected.
> > > Dave
> > >
> > >
> > >
> > > Original poster: "Godfrey Loudner by way of Terry Fritz
> > > <twftesla-at-qwest-dot-net>" <ggreen-at-gwtc-dot-net>
> > >
> > > Hi Dave
> > >
> > > I had a similar problem with an old 7.5kVA industrial 120/240/480
> > > transformer. By paralleling the two 120 windings, I could get up to 60
> > amps
> > > at 120 with a 240 feed. This was a great high current supply for
playing
> > > around with MOTs. One day the transformer went on a dead internal
short
> > and
> > > the breakers tripped. The next day I was very surprised that the
> > transformer
> > > was working, but it shorted again after awhile. I decided to scrap the
> > > transformer for the nice heavy copper wire. After much agony, I
finally
> > > freed the winding from the core. Upon removing the top layer of paper,
I
> > > could see burn marks between two adjacent turns. I think that heat
> > expansion
> > > would eventually push the two weak spots together, and after cooling
off
> > the
> > > weak spots would separate. Maybe something like this is the problem
with
> > > your pole pig.
> > >
> > > When I got my pigs from T&R, I was told that they were under guarantee
> for
> > > one year for normal usage. I forgot to ask if tesla coiling was
> considered
> > > normal.
> > >
> > > Godfrey Loudner
> > >
> > > > What is truly a mystery about this thing is that it either works
> > > perfectly,
> > > > or acts like there is a crowbar dead short across the primary.
Well,
> at
> > > this point, I'm tentatively pronouncing Ariel dead. I'm going to
> > > > call T&R to see if they can supply a replacement core so that I can
> > > perform
> > > > transplant surgery.
> > > > Dave H
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
> >
>
>