Re: Large Tesla Coil Design Help

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

Original poster: "S & J Young" <youngs-at-konnections-dot-net> 

Jim,

With MOTs, PTs or PIGs, just calculate the capacitance needed for your
primary to resonate a few percent below your secondary (with toroid)
resonant frequency.  Use WinTesla or one of the other calculators to get you
in the ball park.  Best to use at least 10 primary turns to reduce gap
losses (more overall efficiency).

With a coil that big, consider going with a six MOT stack, oil immersed for
cooling & extra insulation.  A four MOT stack will probably only produce 8-9
KV.  Also, consider MOTs start drawing many more amps when the primary
voltage goes over about 105-110 volts due to core saturation.  So a six MOT
stack running at 105 volts will be more efficient than a four MOT stack
pushed to 120 or more primary volts.  PFC caps across the primary will also
help reduce primary current.

--Steve Y.

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, February 27, 2004 4:04 PM
Subject: Large Tesla Coil Design Help


 > Original poster: "Jim Mitchell" <electrontube-at-sbcglobal-dot-net>
 >
 > Hello,
 >
 > A friend and I are looking to build a large 10" coil.  We have acsess to
 > MOTs and synchrnous motors etc,  and sonotubes, wire everything to build
 > the coil except the capacitors.
 >
 > Now we were thinking of making a four MOT stack to give around 10,000
 > volts.  The problem is, I have no clue what kind of capacitance will be
 > needed for this coil, or what the LTR for a MOT stack would be.
 >
 > I was thinking of an MMC but with the amount of capacitors im gussing we
 > will need, it will cost 600$ (ha ha)  !!!
 >
 > What would be the best bet for capacitors for this coil?
 >
 > Thank you,
 >
 > Regards - Jim Mitchell
 >
 >
 >