Re: capacitors

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Greg,

The internal loss of all really good Tesla coil caps is so low that it does
not affect the coil.  With a bit more loss, the caps overheat but still not
enough loss to affect the ouput.  When you get near 1 ohm of resistance,
then the Q of the primary drops and the streamers start to suffer.  So any
really good cap performs like anyother.

There is MMC information and a program and details about how to figure out
the currents at:

http://hot-streamer-dot-com/TeslaCoils/MMCInfo/mmcinfo.htm
http://hot-streamer-dot-com/TeslaCoils/MMCInfo/MMCPower4.html
http://www.thegeekgroup-dot-org/Sales/MMCsales.html

Check these out and ask any questions you have.  Many people are now
running MMCs on high power systems.  It used to be a bit pricey but the new
caps are now cheap enough to make big caps very viable.

Cheers,

	Terry



At 02:59 AM 10/7/2001 +1000, you wrote:
>Hey everyone,
>
>As most of you know, I am in the process of building a large coil (up 
>to 10 kVA). I am currently investigating capacitors. I have had it with 
>constructing oil filled rolled or plate poly caps (I've made 6) - too 
>messy, too many hours! I read with interest, some pages where people 
>have used banks (up to a couple of hundred) of commercial polypropylene 
>caps. I was wondering how well these work - are the sparks nice and 
>hot, or thin and purple? I was also after some construction guidelines -
> most of these caps have thin leads, therefore requiring a complex 
>series/parallel arrangement to handle the current. What resistor 
>arrangement is used? How does the polypropylene stack up to LDPE as a 
>dielectric? Are these huge banks alot less efficient then a simple 
>staked plate cap?
>
>Cheers,
>Greg Peters
>Department of Earth Sciences,
>University of Queensland
>
>Phone: 0402 841 677
>
>