RE: Combining several caps

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

Original poster: "Mccauley, Daniel H by way of Terry Fritz <teslalist-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>



Yes, I would agree.  The Geek Group has the best price and offering for MMC
style capacitors.  They have nice programs
to calculate exactly what you need as well as detailed charts.  Plus
customer service is excellent and the caps have
already been proven in numerous designs as being tesla-coil worthy.

Dan




You may wish to do a little reading at www.thegeekgroup-dot-org/mmc I can
supply you caps, and all the reference material you need to design and
build an MMC array.



Christopher "Duck" Boden Geek#1
President / C.E.O. / Alpha Geek
The Geek Group
www.thegeekgroup-dot-org
Because the Geek shall inherit the Earth!

Never doubt that a small group of thoughtful, committed citizens can change
the world. Indeed, it's the only thing that ever has.


The ability to learn is older - as it is also more widespread - than is the
ability to teach.
      - Both from Margaret Mead, 1901 - 1978





 >From: "Tesla list" <tesla-at-pupman-dot-com>
 >To: tesla-at-pupman-dot-com
 >Subject: Re: Combining several caps
 >Date: Thu, 30 Jan 2003 16:39:05 -0700
 >
 >Original poster: "Ramon van der Hilst by way of Terry Fritz
 ><teslalist-at-qwest-dot-net>" <enqrypzion-at-yahoo-dot-com>
 >
 >
 >Today we've measured the NST, and the secundary RMS voltage is 5640,
 >giving a peak voltage of about 8,5 kV. (<I've learned! :D) Actually quite
 >strange numbers, as it's not near the 2x4000 it said, yet the peak is
 >higher.. might this've happened because we measured at an input of 2 VAC,
 >giving an output of 54,8 VAC?
 >
 >well anyway, after taking a better look at some sites about MMC's, I've
 >been searching around for some polypropylene MKP caps. On a postordersite,
 ><http://www.conrad-dot-com>www.conrad-dot-com I found Epcos MKP polypropylene caps
 >with the following specs:
 >
 >  0,15 µF, UN = 630 V=, Ueff = 250 V~, tolerance 5% and 6,0 x 15,0 x 26,5
 > mm (width x height x diameter).
 >
 >I was thinking about buying 50, 10 extra, and using 40 of them. That would
 >give (I've learned again ;-) tnx all!)  0,00375 uF -at- 10 kV, while wintesla
 >and tcc both gave 0,0037 uF as needed capacitance (for 5640V, that is RMS).
 >
 >I was wondering though, as neither of the programs mentioned it, whether
 >you have to fill in the RMS values or the peak values. anyway, are the
 >caps right? (if it's peak voltages then we'll adjust the amount of caps to
 >the right capacitance... as long as it's still 9kV or more).
 >
 >tnx again!
 >
 >
 >
 >  Tesla list <tesla-at-pupman-dot-com> wrote:
 >Original poster: "Sean Taylor by way of Terry Fritz "
 >
 > > We've acquired a NST (sec. : 8kV, 10mA at 220V, 50Hz) and so WinTesla
 > > suggested we use a 4 nF capacitator.
 >
 > > What seemed the simplest for us is using 16 (C1) 1nF 2kV caps, placed in
4
 > > parallel rows of 4 caps in series.
 >
 >SNIP . . .
 >
 >Well, there are a couple problems here. First, the 4 caps in series will
 >total up to exactly 8 kV, where your NST is an 8 kV NST, and will actually
 >put out 11.2 kV on the peaks, plus the ringing in the primary tank circuit
 >will repeatedly reach a high voltage as well. You'll need a cap rated for
 >at least 12 kV. Second, 4 caps in series, while increasing the voltage
 >capability, will decrease the capacitance. Four of your caps in series will
 >be 0.25 nF at 8 kV, so 4 strings of 4 will yield 1 nF a! t 8 kV. You're
best
 >bet for a cap right now would probably be a saltwater cap, easy to make,
 >cheap, and variable size. Someone recently posted the Geek Group bucket cap
 >link, or you can search for it on google. Good luck!
 >
 >Sean Taylor