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Re: DC Coil



At 10:45  21/03/99 -0700, you wrote:
>Original Poster: Chris Tominkson <internetinbox-at-yahoo-dot-com>
>
>Wouldn't a DC coil be  alot easier on capacitors? Since one mil of PE
>will stand 600 volts, you would only need  30 mils to withstand 18,000
>volts.

NO !

I suffered this illusion for a short while too ;-)

Because the cap/inductor "ring" after the discharge (AC or DC), the cap 
will always be exposed to a high freq. alternating field, 50-300 kHz 
depending upon your coil design.

DC does not allow you to lower your guard with capacitor dielectrics:

1.  Use either LDPE or PP
2.  Don't buy cheap plastic.  The cost saving will cost you hours of labour 
and is not worth it.
3.  Use multiple layers in each cap.
4.  Divide the cap into series units & try to get the unit dV to <= 5 kV.
5.  Find a good vacuum pump.
6.  Find a friend to help
7.  Find a clean workshop.

"Light blue touch paper and stand well clear"  ;-)

Remember it is not the 50Hz AC which is the problem.

cheers

mark

(slow learner, but I get there eventually)


Mark

http://www.cobweb-dot-com.au/~dkfinnis