I have to add my 2 cents to this quote below. At my workplace we use
some fairly large oil filled capacitors for energy storage for the
pulsed RF systems. Each B+ supply for klystrons (they don't call it
B+ of course, since it is really a negative supply on the cathode) is
90 kV, with 45 uF of capacitance. We pull a couple hundred Amps of
current for about a millisecond, 120 times/second. If you part your
ear against the steel enclosure (the size of a smaller mobile home or
larger RV) you can hear the ticking of the capacitors as they
mechanically 'jump' during the pulses. A few years ago, this practice
was stopped when end of life failures caused random explosions.
Complete with fire alarms, lotta smoke, and ugly mess on the floor. I
wish they would have failed like Electrolytics as rich noted below.
I have some swell photos of blown up cans if anyone wants to see what
a 4.6 uF, 45KV oil/paper/film cap looks like after it explodes. Let
me know.
73
John
K5PRO
To: <amps@contesting.com>
>Date: Fri, 22 Mar 2002 21:59:48 -0500
>From: wb4mnf <wb4mnf@atl.org>
>To: Peter Chadwick <Peter.Chadwick@zarlink.com>
>CC: w4nul@brightok.net, AMPS <amps@contesting.com>,
> "'Richard'" <2@mail.vcnet.com>
>Subject: Re: [Amps] Henry 2KD Classic
>
>Do not listen for ticking caps with remaining ear...
>
>Peter Chadwick wrote:
>
> > Rich said;
>>
>>
>>>However, if you see white deposits around any of the pressure
>>>vents, the electrolytics are history.
>>>
>>
>> I'd add to that that if you hear a ticking noise from the caps,
>>they're history,
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