RE: Bleeder Resistor Calculation

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

Original poster: "Matt Morrissette by way of Terry Fritz <twftesla-at-qwest-dot-net>" <yinzara-at-MIT.EDU>

Well I know that I need around a 10Mohm resistor for my coil but how do
I know what power rating it needs? I can't seem to find a resistor above
5watts.  That says it can handle 20kV of current. I'm using a 12/60 NST.
Is that alright?  I'm using .0188uF Geek MMC capacitor as well.  What
should I use to bleed these?

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com] 
Sent: Sunday, October 20, 2002 11:54 PM
To: tesla-at-pupman-dot-com
Subject: Re: Bleeder Resistor Calculation

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi,

Bleeder resistors should discharge the MMC in 5 to 15 seconds.  Thus:

10 = 5 x R x C

or

R = 2 / C

That should give a good discharge time without wasting significant power
or
overheating the resistors.

Cheers,

	Terry

At 11:26 PM 10/20/2002 -0400, you wrote:
>> My applied voltage is 15KV, however,
>> I think I need to design for 100KV. 
>
>	CAution is nice, in this cae it can lead to
>	energy inefficiency
>
>> The capacitors will hold 100KV+ before 
>> breaking down, and should they ever get 
>> to these levels (ie spark gap goes kaput)
>> I want to bleed them safely. 
>	Might use an auxiliary spark gap to switch
>
>	in a bleeder in case of massive overvolt.
>
>
>> My goal is to make the most efficient,
>
>	Bleeders can be tricky to make efficient.
>	Designing one set for normal (15kv) with a
>	backup set, only involved, via spark gap,
>	in case of overvolt...
>
>	best
>	dwp
>
>...the net of a million lies...
>	Vernor Vinge
>There are Many Web Sites which Say Many Things.
>	-me
>