Re: what to use for resisters on my bank

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: John <guipenguin@xxxxxxxxx>

Yeah, I would never build a safety gap for a capacitor bank, thats 
like shorting the bank out manually with a screw driver.

What is a good resistance to use? Would you say a series of resistors 
about 10M for every 1 capacitor?

Thanks,

     John.



On 10/5/06, Tesla list <<mailto:tesla@xxxxxxxxxx>tesla@xxxxxxxxxx> wrote:
Original poster: "Lau, Gary" <<mailto:Gary.Lau@xxxxxx>Gary.Lau@xxxxxx>

Since your caps are in parallel, you can't put individual resistors
across each cap, since each resistor must be rated for the total voltage
of the array.  You need to construct a series array of resistors.

I needed a bleeder resistor across my Maxwell cap.  I happened to have a
bunch of 2Meg 1/4W resistors, so I built an array of 39 of them on a
piece of perfboard.  A photo may be seen about half way down on my sync
gap page at 
<http://www.laushaus.com/tesla/sync_gap.htm>http://www.laushaus.com/tesla/sync_gap.htm.

BTW, in the image you referenced on the Powerlabs site, I hope that's
not a "safety" gap in parallel with the caps?  Caps of this type are the
least tolerant of the super-high current that would result from such a
gap firing!  Safety gaps should only be placed in parallel with the main
gap, so that the discharge current is safely limited by the primary
inductance.

Regards, Gary Lau
MA, USA


> Original poster: John <<mailto:guipenguin@xxxxxxxxx>guipenguin@xxxxxxxxx >
>
> I have some strontium titanate caps (yes I know they will slowly
> loose capacitance over time) each rated at about 50kvdc 910pF,
> (safely about ~20 or so kv ac), which I will be using on my first
> coil until I get some mmcs down the road.....
>
> The entire bank will be 0.01uF. My bank will look (similar) to this
>
<<http://www.powerlabs.org/images/tccapbank.jpg>http://www.powerlabs.org/images/tccapbank.jpg  
>http://www.powerlabs.org/
image
> s/tccapbank.jpg
> between two sheets of Lexan.
>
> what should I do about resisters like I see on all mmc banks?
>