capacitor voltage question

[olivergreen]

Hi maybe any one can help me.
I have an old power supply with some old capacitors.
I want to remove them and replace them with some new.

My question is :
One of them is a 12000 uf 16 V
Can I use a 12000 uf 77 V ...

Or do I have to find a 12000 uf 16 V

Oliver

 

[MikeMl]

It will work, but I would try to find one where the Working Voltage rating is a little closer to what exists in your circuit. AFAIK, if electrolytics are operated far below their WV rating, they do not "form" their dielectric properly.

 

[olivergreen]

Thanks for quick reply..

I will try find one closer to the old one then.

Oliver

 

[BrownOut]

It will work, but I would try to find one where the Working Voltage rating is a little closer to what exists in your circuit. AFAIK, if electrolytics are operated far below their WV rating, they do not "form" their dielectric properly.

I'm surprised all the "experts" haven't gone bezerk as they did when I said the same thing

 

[Vizier87]

It's kinda frustrating... When I say to the shopkeepers "I wanna 10 1uF caps, blah blah blah" and I get these small ones with a 50V rating. I wonder if this is significant? For electronics with 12V supply...

 

[olivergreen]

Yes...
You'r right that's why I ask this question.
If you take a look in your junk box I'am sure you will find
some 10uf 16V in two or three size, a big one, a little
one, a tinny tinny one all with the same value.

And it's the same with this Ceramic Capacitors, a 104
can be as little as 4 mm and as big as 10 mm.

And here a new question come up to my mind ...
If You have a big 10uf 16V in your circuit ..can you
replace it with a tinny one with same value ?

I do understand What MikeMl explain about "dielectric"
And why it is necessary to find a capacitor as close as posible
to the old one.

Oliver