Re: TI-H: Caps

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Re: TI-H: Caps


On Fri, 17 Apr 1998, Chris Cooper wrote:

> Is there any way to see if a capaciter is working, and what the rating is?

A $90 meter will do it too..

But anyway, a capacitor functions by charging and discharging, right? If
the cap has a large enough capacity, you could charge it with about 2
volts and then put an LED on it. If the LED blinks, then the cap is
working.

You can also test it by checking how much current it draws. A good
capacitor should draw a little current and then stop drawing. A bad cap
will either be shorted or will be open. If it is shorted, then there will
be nearly 0 ohms resistance and it'll draw a lot of current. If it is
open, it will not draw any current at all.

Of course, if you've got a very small cap you might not be able to see the
current being pulled anyway.. unless you have a very accurate analog
meter. A very good digital meter might be able to catch the current
spike.. but it'd be very expensive too.

-- 
Greg Hill
greg-hill@bigfoot.com
www.comports.com/link
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