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dave dave is offline
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Default Small Capacitors: What Numbers Critical?

On 04/07/2014 07:08 AM, RobertMacy wrote:
On Mon, 07 Apr 2014 06:30:39 -0700, (PeteCresswell) wrote:

I've got a couple of IP cams where the same cap failed.

It's a 15 uF, 100v radial cap spec'd to 105c.

But I'm having fits trying to find a replacement where they don't rape
me on shipping.

Can I shop for something with slightly different specs?

i.e. is 100v just an upper limit beyond which the cap will fail... and I
could replace it with a 200v or 300v cap?

What about uF? Do I use a 20 or 30 uF at my own risk?


Depends a bit on failure mode.

same cap, same location? probably being overstressed either with
voltage, which isn't likely because designers understand voltage, but
overstressed with excessivae AC ripple current, since most designers
don't understand that stuff and simply spec for high temp, like 105C --
you see the thought process here?

Therefore *IF* you replace go for same or more uF, same or more voltage
[tilt towards more voltage], and definitely LOWEST Resr you can find.
...my opinion only, without looking deeper.


Is this an electrolytic? Polarized?