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Re: Capasitor match

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

On Mon, 14 Feb 2000 21:31:55 -0700 Tesla List <tesla-at-pupman-dot-com> writes:
> Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
> 
> Hi Bryan,
> 
> 	There are three basic capacitor sizes:
> 
> 1	Resonant.  This is the size that will resonant with the 
> transformer at
> 60Hz allowing fairly high power transfer.  You will get more that 
> 120
> breaks per second.  Safety gaps are an absolute must because if 
> anything
> goes wrong the voltage can jump up to like 50,000 volts and blow 
> everything
> up.  These are very popular but they have left many dead NSTs in 
> their wake.
> 
> 2	"Big"(I just made that up)  This cap size is about 50% 
> large than a
> resonant cap and has fewer BPS but the larger cap makes up for it.  
> It is
> far less likely to destroy anything if something goes wrong.  I 
> would
> recommend this.  Many would consider this as an "LTR" type but I 
> like to
> reserve that for the really optimized coils.
> 
> 3 	"LTR" Larger Than Resonant.  The cap size is the maximum 
> that can be
> charged at the line frequency.  This usually takes advantage of the 
> timing
> of a rotary sync gap to work.  Very safe and has very good power but 
> fairly
> complex to figure out and build.
> 
> These are all for NST systems that have current limited 
> transformers.
> Other transformers have other considerations.  Let us know what kind 
> of
> transformer you have and a little detail on your coil and we can be 
> more
> specific.
> 
> Cheers,
> 
> 	Terry
> 
> 
> At 07:23 PM 02/14/2000 -0500, you wrote:
> >Hello everyone,
> >      I am building my first capasitor.  I know you want to try to 
> match the 
> >capacitance of the capacitor with the transformer, but is it okay 
> to go
> over.  
> >Is there any advantages/disadvantages to haveing a larger 
> capacitor?  Thanks 
> >for any help.
> >
> >
> >
> >Bryan Miller
> >
>