Re: Capasitor match

To: tesla-at-pupman-dot-com
Subject: Re: Capasitor match
From: Terry Fritz <twftesla-at-uswest-dot-net>
Date: Tue, 15 Feb 2000 17:26:12 -0700
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme
In-Reply-To: <20000215.104808.-3718721.1.ronwes1-at-juno-dot-com>

Hi Ron,

Wow! Real data ;-))  That helps!

Your fundamental frequency will be around 300kHz with the primary taped at
8.5 turns.  The resonant cap size is 5.3nF.

If you want 120 BPS operation, Each bang will draw 3.75 joules from your
450VA transformer (450/120=3.75).  Assuming a 21kV firing voltage gives
17nF for a primary cap size (3.75 = 0.5 x C x V^2).  

So you want a 17nF, 21kV peak cap that can take 300kHz at 120BPS.  Using my
new program....

MMC Calculator  Ver. 1.1  2/15/2000  Terry Fritz
Firing voltage =  21000 
Fo =  300000 
Break rate =  120 
Cap value =  5.6E-08 
Strings   Caps/String   Total Value   Temperature   Cost
  3        10            16.80         7.56          43.50  Safe
  4        13            17.23         4.47          75.40  Very Safe
  5        16            17.50         2.95         116.00  Very Safe
  5        17            16.47         2.62         123.25  Very Safe

So you would want the 3 x 10 or 4 x 13.  

You can fix it so you can select any string to get three or four values.
If you wanted you could go for a higher value cap so you could select many
values... 

Strings   Caps/String   Total Value   Temperature   Cost
  5        10            28.00         7.56          72.50  Safe
  6        12            28.00         5.25         104.40  Safe

The 5 x 10 could go from 5.6nF to 28nF in 5.6nF steps and really cover many
NST ranges for $30 more.  You can always leave room for extra caps in the
future too.  I run my 15/60 LTR system with a 5 x 10 MMC.

http://www.peakpeak-dot-com/~terryf/tesla/misc/ltr/

I am going to get a lot of mileage out of my new program ;-)))

http://www.peakpeak-dot-com/~terryf/tesla/misc/MMCCALC1.ZIP

Cheers,

	Terry

At 10:48 AM 02/15/2000 -0800, you wrote:
>Terry,
>In my case I am building my first coil.  I have the primary, 11-1/2 turns
>of 1/4" copper tubing spaced on 1/2" centers (about 7" inside and 18"
>outside diameter) and the secondary, 4" coil form with 21.2" of 22 AWG
>polyamide-imide magnet wire.  My power will come from either a
>Franceformer 15KV 30mA or a Johnson Electric 15KV 30mA (or maybe both in
>parallel).  I had planned on a MMC rated at 24KV and 0.0112 uF total.  Is
>this a good cap design?  Using 45 of your poly caps I figured three
>strings of 15 serially connected caps would do it?
>
>Ron
>