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RE: what to use for resisters on my bank



Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>

<Snip>

Calculating the bleeder:

First of all, calculate a reasonable time for the pack to discharge without
biting you. That is simply R*C*5 so let's take say 300,000,000 resistance *
.00000001 cap * 5 = 15 seconds to be near zero. Ok, so you wait 15 seconds.
Power: is simply E^2/R=P in watts. Lets say you are using
15,000volts*15,000= 225,000,000/300,000,000 =.75 watts lets say you use (3)
100meg resisters in series .75/3=.25 watts per resistor (for illustration).
It would be safer to use more, smaller resistors.

I think that's the jist of it. BTW 15 secs is considered a bit long I
believe.
Jim Mora

 > Original poster: John <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/
image
 > s/tccapbank.jpg
 > between two sheets of Lexan.
 >
 > what should I do about resisters like I see on all mmc banks?
>