Re: Sonderman Testing

To: tesla-at-pupman-dot-com
Subject: Re: Sonderman Testing
From: Tesla List <mod1-at-pupman-dot-com>
Date: Sun, 28 Sep 1997 14:16:34 -0600 (MDT)
Approved: mod1-at-poodle.pupman-dot-com


---------- Forwarded message ----------
Date: Sun, 28 Sep 1997 12:21:40 -0400
From: "Edward J. Wingate" <ewing7-at-frontiernet-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Sonderman Testing (fwd)

Tesla List wrote:
> 
> ---------- Forwarded message ----------
> Date: Fri, 26 Sep 1997 18:47:25 -0400 (EDT)
> From: Esondrmn-at-aol-dot-com
> To: tesla-at-pupman-dot-com
> Subject: Sonderman Testing

<snip>
> Now I opened up the safety gap across the capacitor to about 1.0".  I was
> very surprised to find out that I could only open up the variac to maybe 60%
> of full power before the safety gap across the cap started firing again.  It
> must be in tune, why is the safety gap firing????
> 
> I turned the variac down a small amount where it would run without firing the
> safety gap.  Increasing the primary current produces hotter sparks up to a
> point then at full current, the spark length falls off noticeably.  This is
> puzzeling.
> 
> Increasing the rotary gap speed causes hotter sparks for a while and then
> falls off past a certain point.  This is unlike my past experience where this
> coil was hungry for power and would continue to produce better sparks as I
> increased the rotor speed - as fast as I dared turn it up.
> 
> I could certainly use some help here.  This coil used to produce 80"
> discharges and now I can't seem to get past about 36" to 40".  Something is
> not right and I can't find it.  If the primary and secondary are in tune, why
> can't I apply full voltage?  I have the rotary gap across the high voltage
> mains, should I swap it with the cap and put the cap across the mains and let
> the rotary act as a safety gap for the cap - and remove the existing safety
> gap across the cap - as Peter E. suggested the other day?  I really can't
> afford to blow up any more capacitors.  By the way, the main safety gaps
> connected near the output of the pig, with the center post grounded, never
> did fire in any of these tests.  It never has fired very often in the past
> unless I was getting secondary hits down into the primary.
> 
> Thanks,  Ed Sonderman

Hi Ed,

Your safety gap across the cap is telling you that something is wrong
and still you are considering removing it? Interesting approach!
Especially in light of your past experiences with blown caps.

A fixed main gap can afford -some- protection for the cap but a rotary
will NOT. The maximum total gap of a spinning rotary is far greater than
is required to protect a 15 - 20 KVAC cap. With any two adjacent
spinning electrodes on the rotor equidistant from the stationaries this
gap would normally be the distance between the stationaries around the
edge of the rotor on a rotary with a single set of stationaries. Of
course this distance will vary depending on the design and configuration
of the rotary, but you get the point.

Locating problems in an ailing coil can be frustrating to be sure. And
it is difficult to diagnose a coil from a distance through the printed
word. I am assuming you have checked obvious things such as coupling
factor and have experimented with gap settings on the rotary. I don't
remember if you stated in the past whether or not you are using chokes.
If you are, don't locate them anywhere near the primary. In fact you are
better off not using them at all with a pole transformer.


Safe Coiling,

Ed Wingate