Re: rectifier stack experts?

["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>

At 07:51 AM 10/21/2002 -0600, you wrote:
>Original poster: "Craig Fuller by way of Terry Fritz <twftesla-at-qwest-dot-net>" 
><cbfull-at-hotmail-dot-com>
>
>Ken,
>
>While reading a power supply design book some time ago, I learned that you
>can rectify the voltage using peak-to-peak values, with some percentage of
>over rating.  That's 15kV times 1.414 = 21,213V times 1.1 for 10% safety
>margin (you should probably go higher than 10%).  Now here's the part that
>most overlook.  If you are connecting this to a capacitor, you need to
>multiply this number by 2 AGAIN because once the cap is fully charged, the
>peak voltage will tend to ADD to the cap voltage (i.e. 21,213 times 2, or
>42,426 volts!)  This makes sense when you think about it.

Think of it when the output of the transformer is opposite in polarity from 
that on the capacitor.. 2*Vpeak..

Bear in mind, though, that if you are using a bridge rectifier, you have 
two diodes in series, so each diode really only needs to be rated for Vpeak 
(plus margin!).