[sdiy] Why Electrolytics?

[Magnus Danielson]

From: Cynthia Webster <cynthia.webster at gte.net>
Subject: [sdiy] Why Electrolytics?
Date: Tue, 21 May 2002 13:48:34 -0700

> With all these age related failures
> is there any reason to ever use Electrolytics?

Amount of capacitance per volume, price and voltage in many
cases. Another is naturally habbit.

There are many tricks you can play to increase the MTBF on
electrolytics, but it seems most uses them without too much thought on
the subject. I'm not a living expert on electrolyts, but there is a
few simple things you can do at least to save the lyts ass...

But, for very long periods of life, I look on replacing lyts as normal
maintenance. Replacing them after 10-15 years is usually not very
expensive, and not frequently enougth to be very annoying. Most people
change cars more often than that.

>From the top of my head a few things I recall (OK, don't shoot me for
having not read the thread all that well...):

- Avoid excess heat - caps dry up
- Use caps with temperature rating beyond your needs
- Avoid reverse polarity, both for DC and short spikes. Shunt the caps
  with a small plastic or even quick cheramic cap to help eat spikes.
- Some electrolytics should be conditioned with charge for some time
  before they can handle full voltage rating if they have not been in
  use for some time.

I am sure people can come up with more, I would certainly need some
more research into the topic (which I would be happy to do when I get
some spare time on my hands... oups, halting logic!).

> Is there a more bullet proof equivalent capacitor to use instead?

Depends on the application!

Cheers,
Magnus