Re: Shorting caps

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

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

As a general rule, a safety bleeder should be chosen to get the voltage
below 50V in some reasonable time (say, 30 seconds)...


If the cap is charged to 20kV, to get down to 50V is a reduction by a
factor of 400.  That's roughly 6 RC time constants.  Using 30 seconds,
you'd want one RC time constant to be 5 seconds.  If your cap is, say, 0.01
uF (1E-8 Farad), you'd want your bleeder to be around 5/1E-8 or 50 Megohms...  

1 RC constant 1:2.7
2 RC constants 1:7.4
3 RC constants 1:20
4 RC constants 1:55
5 RC constants 1:148
6 RC constants 1:403

Tesla list wrote:
> 
> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Dan_Gallagher%PULSARNOTES-at-pulsartech-dot-com>
> 
> Hi sparkers,
> What kind/value of bleeder resistors go across the HV caps? I'll be
> building at least one SW bucket cap soon and after reading all these posts
> I don't want to leave this cap lying around charged up and someone else
> said not to short it out.
> 
> As always I appreciate your input and guidance.
> ps. Any teslathons in South Florida?
> 
> Getting Closer...............
> Dan
> Ft. Lauderdale