[Boatanchors] [BoatAnchors] Electrolytics- How Much is Too Much

[J. Forster]

IMO, the trend is the important factor, unless the leakage is high enough
to cause noticable self-heating.

-John

================



> When I was in the high power amplifier business, we tested all our caps
> for leakage and actually matched them, since we made series strings.  Our
> capacitor vendor said we were going overboard because we used equalizing
> resistors anyway, so mismatched leakage would be swamped by them.  But we
> went overboard in a lot of areas on our amplifier.
>
> Our "failure criteria" was one of drift.  The leakage, one day after
> starting the test, had to be half or less of the starting value, and after
> one week, it must not rise - ever.  Ours were 650uF 450V "computer style"
> electrolytics, and it was unusual for us to see leakage above 250uA.
> Older technology may leak more.
>
> Dave W8NF
>
> --- On Thu, 1/31/13, john <johnmb at nc.rr.com> wrote:
>
>> From: john <johnmb at nc.rr.com>
>> Subject: Re: [Boatanchors] [BoatAnchors] Electrolytics- How Much is Too
>> Much
>> To: "David Stinson" <arc5 at ix.netcom.com>, boatanchors at theporch.com,
>> boatanchors at mailman.qth.net
>> Date: Thursday, January 31, 2013, 2:14 PM
>> I've always used the "old standards"
>> (Radiotron Handbook), where there's a
>> formula I can't remember right now. What you observe doesn't
>> look
>> excessive, though It probably would be more comforting to
>> know if it's ONE
>> of those sections doing the leaking or is it ~ evenly
>> balanced.
>>
>> John
>>
>>
>>
>> At 06:59 AM 1/30/2013, David Stinson wrote:
>> >High Voltage electrolytics- how much current leakage
>> >at rated voltage is "too much?"
>> >
>> >There are old standards published 70 years ago,
>> >but I'm interested in your current insight.
>> >Say- I have an original can capacitor, rated 40-40-40 at
>> 450 volts.
>> >After sitting with all three tied together and at
>> >400 volts, total leakage was about 1.5. mA.
>> >
>> >I'm not interested in re-igniting the nasty
>> name-calling
>> >over whether or not "re-forming" caps is a good or bad
>> idea- only in what
>> >level of leakage is, in your opinion,
>> >acceptable in order to maintain a stock part in a set.
>> >
>> >73 DE Dave AB5S
>> >
>> >_______________________________________________
>> >BoatAnchors mailing list
>> >BoatAnchors at theporch.com
>> >https://minime.theporch.com/mailman/listinfo/boatanchors
>>
>> ______________________________________________________________
>> Boatanchors mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Boatanchors at mailman.qth.net
>>
>> List Administrator: Duane Fischer, W8DBF
>> ** For Assistance: dfischer at usol.com **
>>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
> ______________________________________________________________
> Boatanchors mailing list
> Home: http://mailman.qth.net/mailman/listinfo/boatanchors
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Boatanchors at mailman.qth.net
>
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
>
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>