How old are those "new" ones Eddy? Knowing you they are 1960's surplus!
Reforming is often only temporary and some significant leakage will
return with use.
Use a low value equalizing resistor; 30-50K @ 10W and place far enough
away so the caps dont get the heat.
Over time do a regular PM and feel the caps for excessive
heating.......after discharged!
Carl
KM1H
----- Original Message -----
From: "EP Swynar" <gswynar@durham.net>
To: <amps@contesting.com>
Sent: Wednesday, October 22, 2008 1:59 PM
Subject: [Amps] High-Voltage Electrolytic Capacitors
> Good Day All,
>
> I blew a fuse in my 2x813 HB kilowatt the other day, due to a shorted
> electrolytic capacitor in the filter "string" of the 2500-volts B+
> p.s. (the darn things are some 30 years old already, and owe me
> nothing!).
>
> Anyway, scrounging through my junque box revealed a beautiful set of 8
> matching aluminum canned electolytics (220-pfd. at 350 WVDC) that will
> make a dandy back-up "plug & play" filter. I'm presently in the
> process of "re-forming" them all, one by one, and it still continues
> to amaze me just how long some of them take to "heal"...literally,
> hours.
>
> I can only imagine what would sort of an explosion(s) may well have
> ensued, had I elected to simply "plug in" the new filter bank after
> the rectifiers, without first going through this process...
>
> It's tiresome, tedious work, but SOMEONE has to do it, I guess, Hi Hi
>
> ~73~ Eddy VE3CUI - VE3XZ
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>
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