[sdiy] [ot/3] Using ElectrolytCapacitors

[Scott Bernardi]

If you want to make a capacitance larger, you put them in parallel. Then
you add the capacitances.
       +-----[]!-----+
       |                  |
-----+                 +-----
       |                  |
       +-----[]!-----+

Note that electrolytic capacitors are polarized - they have a plus and
minus side. When putting them in parallel, make sure the minus sides are
connected together!
The connection you showed is a series connection. This is what you do if
you want a non-polarized capacitance, which is probably what you mean by
you need to use it in an ac line. What you showed will work, but the total
capacitance will be half of each individual capacitor (if you use equal
capacitors). So if you need 470uF total, you'll need to use two 1000uF in
series (to get 500uF).
Also, electrolytics have breakdown voltages you have to be aware of.  In a
parallel arrangement, the breakdown voltage will be the same as that of the
lowest capacitor B.V.  In the series combination, they add.


Timo Weggen wrote:

> Hello,
>
> first, I'm no engeneer, I don't know very much about electronics, but I
> am eager to learn. Thus I listen what you all write here.
> Now, in an experimental circuit, I need quite beeg (470uF) capacitors
> in a AC line.
> My father told me recently, he'd used successfully used ElectrolytCaps
> like that, and it worked:
>
> ---[]!--![]----
>
> (Instead of a single hige --||--)
>
> But I am not sure I got it right, and I also want to understand it.
>
> TIA
>
> Timo

--
Scott Bernardi
sbernardi at home.net