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Re: DC power supplies etc.
Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>
How much ripple can you tolerate? 10 uF is a lot of capacitance, at, say 10
kV and 100 mA...
Ripple = deltaT * I / C (roughly)...
100 mA, 8.6 mSec period, 1 uF = ca 900 V ripple... 10 uF = 90 V ripple...
(<1 % out of 10 kV....)
I might also add that the hazard of 500 Joules stored in a low impedance
source (that 10 uF cap) is signficant. A short circuit or inadvertent
flashover will probably "break parts".
Inductive filters might be a better way to go
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
Sent: Sunday, December 23, 2001 1:44 PM
Subject: Re: DC power supplies etc.
> Original poster: "Mike Nolley by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> > USA Manufacturing Surplus (http://www.usamfg-dot-net/) has microwave oven
> > (2100 VAC or about 3 KV DC at 1 uF) for 50 cents each which is a good
> > Look in their on line catalog under capacitors. They also have some
> > volt 3 uF caps for 50 cents. At these prices, you can gang a bunch of
> > in series/parallel for DC power supply use.
> > --Steve
> That's a pretty good price, I might look into buying some of those.
> you know of a manufacturer
> that sells good quality diodes at those prices?
> There is also an issue with the oven caps as filter devices. They are
> great for doubling
> purposes, but the filter capacitors need to handle the full voltage of the
> power supply--12kv or so.
> To get a capacitor of the required voltage and with sufficient ripple
> reduction (say 10uf) you would
> need... 216 capacitors. Thats $108.