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Re: HV caps, idea...
Subject:
Re: HV caps, idea...
Date:
Fri, 21 Mar 1997 22:58:39 +0200 (EET)
From:
Harri Suomalainen <haba-at-cc.hut.fi>
To:
Tesla List <tesla-at-pupman-dot-com>
On Tue, 18 Mar 1997, Tesla List wrote:
> Power supply ceramic caps come at 0.1uF 1200V.
> can i use 20 if these in series to create a capacitor, or it it
> better building a botle cap or poly cap by myself ?
If you put many in series you will get more voltage handling capability.
However, if they are not high-tolerance caps it will not be exactly the
multiple of caps in series. Say you have one with -10% and others at
+10%
capasitance. Calculate the wors case situation like that yourself.
You may also get problems with leakage, try paralleling them with
suitable resistors to be absolutely sure leakage cannot make one charge
more than the others. (The cap with least leakage gets highest voltage)
The worst is that usual ceramics cannot handle large amounts of
rf power. They are too lossy. You would definately like some low-esr
caps. Remember also that if each cap has ESR of say 0.1 ohms and you
put 10 caps in series the total ESR will then be 1 ohm.
--
"99% of the pain in the world is due to misunderstanding" -M.
Jarvelainen
Harri.Suomalainen-at-hut.fi - PGP key available by fingering
haba-at-alpha.hut.fi