Re: Primary / Secondary Diameters

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

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Parpp807-at-aol-dot-com>

In a message dated 1/18/01 9:29:37 AM Central Standard Time, tesla-at-pupman-dot-com 
writes:

<< Subj:     Re: Primary / Secondary Diameters
 Date:  1/18/01 9:29:37 AM Central Standard Time
 From:  tesla-at-pupman-dot-com (Tesla list)
 To:    tesla-at-pupman-dot-com
 
 Original poster: "Barton B. Anderson by way of Terry Fritz 
<twftesla-at-uswest-dot-net>" <tesla123-at-pacbell-dot-net>
 
 Hi Ralph, 
 
 >> However, arc-over distance is horse of a different
 color. 
 
 Arcing between primary and secondary is primarily determined by the primary
 wire radius of curvature, the distance between primary and secondary, and the
 potential. The secondary should be seen as a large ROC at the size of the
 secondary form due to the close proximity of the windings. I beleive there 
is a
 paper at Terry's website identifying arc potentials in air using different
 voltages and sphere's that could serve as a guide (or trial and error will do
 the trick to). I'm not exactly sure where the paper is located at the site. 
 
 Take care, 
 Bart<<<<<<<<
 
 Hi Antonio and Bart,
Thanks for the help with my bipolar pri / sec coil spacing. I was aware of 
the ACMI
program. Gyrating in my cranial vacuum was the notion that the arcover 
between the helical 
primary and the bipolar secondary is not just a coupling coefficient problem, 
but I couldn't get the
idea together. Terry sez that the web site you refer to is nothing more than 
the standard spark gap data, and that's what it is. But I have always 
considered the SG data as applying to a steady E
field at various pressures and temps, and not descriptive of the interruptive 
spark pulse and
subsequent ringdown where the instantaneous voltage is so very large.  So if 
I am wrong, I'm not far from it.  :-))
Therefore, it seems that my 1.5 to 2 inch spacing based on trial and error is 
close to the answer.

I am around a week away from firing up my 48 inch bipolar and I will proclaim 
the details when
I get it going. Thanks again for your help.

Cheers,
Ralph Zekelman