NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/rec/audio/car/4883

Text File | 1992-11-17 | 1.8 KB | 46 lines

Newsgroups: rec.audio.car
Path: sparky!uunet!mdisea!uw-coco!quick!ole!ssave
From: [e-mail] (The Devil Reincarnate)
Subject: Re: 1 Farad Capacitor availability
Message-ID: <[e-mail]>
Organization: Cascade Design Automation, Bellevue, WA
References: <[e-mail]> <[e-mail]>
Date: Mon, 16 Nov 1992 22:18:33 GMT
Lines: 35

In article <[e-mail]> [e-mail] (Kirk Lindstrom) writes:
>}>   Right now i'm looking in the new Pasco Scientific Physics catalog and
>}>they have for sale a 1 farad capacitor for roughly $19.00.
>}>The problem is is that it is a 5 volt and not a 12-20 volt as needed for
>}>automotive use.  Does anybody have any idea how to get a 5volt to work
>}>with 12-15 volts?  If so then these would be a lot cheaper than the
>}>800,000 microfarad that 2000 sells for $125.00...
>}>
>}>                                   William C. Devine, II
>}----------
>}Stack 4 in series and you get a 0.25 Farad capacitor for 4x$19 or $76 that
>}is rated at 20 Volts.  Of course it will take up alot of space.
>}

    I don't think that this is a very good idea. A capacitor is basically
a short circuit for transients. What this means, is that whenever you get
a transient, the four capacitors will have to short through, only if three
of them stay shorted for even a slightly longer time than the other,
you will have a full 20V across one rated at only 5V.

    I don't know what the dielectric in them is, but it should be something
like oil, and I wouldn't want that blowing up in my face.

    Think.

    -Shailendra
    [e-mail]

>}I saw an add in some parts mag. for 0.1F 20V caps for $18.95.  I'm
>}thinking this might be a good buy.  Size is 2.5"Dia. x 4"Long.
>}
>}Kirk out
>----------