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From: dave@onfcanim.UUCP (Dave Martindale)
Newsgroups: net.analog
Subject: Re: Effect of overvoltage on electrolytic capacitor (summary)
Message-ID: <14930@onfcanim.UUCP>
Date: Fri, 19-Sep-86 09:59:08 EDT
Article-I.D.: onfcanim.14930
Posted: Fri Sep 19 09:59:08 1986
Date-Received: Sun, 21-Sep-86 22:07:13 EDT
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Organization: National Film Board / Office national du film, Montreal
Lines: 19

Well, I've received a number of replies by now (over half of them from
Tektronix!).

The concensus is that the stress of working at a higher-than-rated
voltage will greatly shorten the life of the capacitor.  No one predicted
it would explode (unless the voltage applied was increased to twice its
working voltage).  Someone phrased it as "when you select a capacitor's
voltage rating, you are really selecting its wear-our rate".

It seems that general practice is to use a capacitor which is overrated
by about 50% - so a 30V rather than 15V capacitor is appropriate to
this application.

I'll replace the capacitor before I actually put the piece of equipment
into service.  (I've only been testing it so far).

Thanks to all those who replied.

	Dave Martindale