Re: InnerDiameter of Primary Coil.

To: tesla-at-pupman-dot-com
Subject: Re: InnerDiameter of Primary Coil.
From: Bert Hickman <bert.hickman-at-aquila-dot-com> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Tue, 06 Jul 1999 12:19:05 -0600
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

Tesla List wrote:
> 
> Original Poster: ARSONIST01-at-aol-dot-com
> 
> Does anyone know if the size of the inner diamter of a primary coil would
> affect performance? Currently i'm building the primary and i have planned to
> use an 8" diameter to fit my 6" secondary in between it. But, i have just
> obtained some 8" diameter pvc and i would like to fit a 8" secondary on my
> coil. In order to do that, my primary would need to have a 10" inner
> diameter. Now the big question is.. would the primary w/ a 10" diamter and a
> 6" secondary work the same as a 8" primary and 6" secondary?
> Thanks ahead,
> alan

Alan,

Many new coilers make the error of not providing sufficient clearance
between the innermost primary turn and the secondary. This leads to
primary-to-secondary flashovers at the base of the coil, sometimes
damaging the secondary or destroying the Neon Sign Transformer. Provide
AT LEAST 1.5" of clearance all around the secondary - in your case
making the innermost primary diameter at least 11". If you provide
significantly more than 1.5" of clearance, the system will still operate
properly, but you may need to raise the primary height a bit (or lower
the secondary) to maintain the same degree of coupling.

-- Bert --