Re: Overstessing Maxwell caps

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 7/21/01 10:43:25 PM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

> Original poster: "Steve White by way of Terry Fritz <twftesla-at-qwest-dot-net>" <
> slwhite-at-zeus.ia-dot-net>
>  
>  I have two 0.03 uF Maxwell caps rated at 35 KV each. I was planning to 
> connect
>  them in parallel to obtain 0.06 uF for my pig coil which I am currently
>  building. The pig puts out 14,400 volts RMS. I am now beginning to wonder 
if
>  the 35 KV voltage rating for the 2 parallel caps is enough. I theoretically
>  have about a 2x safety factor. I have been reading that 3x is preferable. 
My
>  design requires about 0.06 uF of capacitance. Should I go ahead and use 
> these
>  caps (I paid quite a bit for them) or should I sell them and build a MMC 
> array
>  instead? Alternatively, I could turn my variac some to a voltage 
sufficient 
> to
>  obtain a 3x safety factor.
>  

Steve,

The answer depends on how long you want your sparks
to be.  If you can achieve the desired spark length with the variac
turned down, then I'd recommend that method.  If you need longer
sparks that will require the full variac setting, then it would be safer
to get different caps, or put the caps in series, and run at a higher
breakrate, to achieve power thoughput in that way.  I've run the full
fury of a 14.4kV PT into a 45kV rated Maxwell, but not into a 35kV 
rated one.

John Freau