Re: heating a cap

On Fri, 04 Oct 2024 12:10:38 -0400, legg <legg@nospam.magma.ca> wrote:

On Thu, 03 Oct 2024 16:36:24 -0700, john larkin <jl@glen--canyon.com>
wrote:
>

I got a small (under 1" long) aluminum electro cap, 220 uF 63v, and
cranked up the voltage. It started drawing a bunch of current at 105
volts, got hot, and folded back to 80 mA at 87v.
>
It got too hot to touch in a couple of minutes, after roughly 500
joules. Freeze spray let it go back up to 100 volts or so.
>
None of that seemed to damage it, so an electrolytic cap sort of has a
built-in MOV.

>
You're not 'heating a cap'.

Felt hot to me.

>
You're applying voltage overstress to failure, using a
current limited source.

But it didn't fail.

>
This tells you precisely nothing.

Told me a lot. Why elect to not learn things?

>
Were you earing safety glasses?

No earrings, and my normal glasses.

>
Are you sure you want to advertize this increasingly
erratic behavior?

Experimenting with parts is admittedly a bizarre thing for an engineer
to do. Sorry.

>
RL