Re: Fried Caps? (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Fri, 26 Oct 2007 12:01:23 +0100
From: Mike Tucknott <michael.tucknott@xxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Fried Caps? (fwd)

Hi Victor

Looks like a case of cap over voltage, a few things you might like to try is
to keep
all the strings of caps the same distance apart also most MMC banks use a
10meg Ohm
bleed resistor across each cap this help to stablize the voltage across each
one.

I think Terry might be able to help, I`m not to sure about the type of caps
you are using.

If it's OK with you I'd love to add your burned and dead cap picture to our
web site.

Cheers Mike Tucknott

>
>  Hi,
>
>   I have a pretty basic TC that I built
> a couple of years ago.  It worked great
> in the beginning but I am having issues
> with the Tank Cap.  Here are the
> design parameters:
>
> NST 12Kv, 30mA
> Spark Gap: copper tube-based, 9 gaps with @20 mils/gap
> Tank Capacitor: 77x GE 42L 3kv, (7 strings of 11 caps) (.0066 uF total)
> Secondary Coil - 3.25" diameter, 801 turns 24 awg wire
> Top Load: 4.5" diameter aluminum ducting. total dia = 15"
>
> The problem I am having is that random capacitors just seem
> to heat up, melt, and/or catch on fire (lovely show, pic
> attached)
>
> Should I reduce my gap?  I thought that a 12kv
> input with 33kv for each cap string would be enough of
> a safety factor.  Is there some minimum spacing
> I should keep between the adjacent capacitors and/or
> the caps in the next string?
>
> Victor
>
>
>
> _______________________________________________
> Join Excite! - http://www.excite.com
> The most personalized portal on the Web!
>