Using Polarized CAPs in AC

[joe_1]

Hi:

I am just wondering what will happen if I connect an electrolytic polarized cap to an AC line.
I know that connecting the wrong polarity to a polarized cap might cause it to explode, and in AC, the polarity is changing all the time.

Thanks.

 

[dknguyen]

Did you just not answer your own question?

 

[joe_1]

I have very good "theoretical" idea about what will happen, so it is some sort of confirmation that I was looking for.

 

[HarveyH42]

Explosion kind of depends on the voltage rating of the capacitor...

 

[Leftyretro]

There is a way.

By connecting two electrolytic polarized caps in series with + to + and input and output using the negative leads, one can use the resulting capacitor in a AC circuit. Of course the total capacitance will be less then either individual value. Two 10mfd caps in series will present a 5mfd value, calculated just like having two resistors in parallel.

Edit: You still have to spec the working voltage of the caps to the application voltage.

Lefty

 

[Robot builder 101]

mfd? Do you mean uf (microfarad)? You have that posted as millifarad.

 

[Hero999]

Some older publications use m to stand for micro which is pretty silly in my opinion, but it's only used for capacitors which aren't normally found it values as high as 1mF so it doesn't cause too much confusion. I never use mF, I normally use :mu:F for values =<99,999:mu:F and Farads for values >=0.1F, that way I never get confused.