Caps in amps

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"Scott Dorsey"
> Phil Allison <
> >
> > BTW Can you verify ( for Arny's benefit) that heating an electro
reduces
> >the ESR reading ?
> >
> > Using a hot air gun on a cap ( say 47 uF, 350 volt) while connected to
the
> >meter.
>
> Sure it does.


** By what ratio though ???

I see about a 5:1 reduction.


> But it'll also reduce the measured capacitance value with
> a DMM too.


** Bunkum - electros have a positive tempco of capacitance .


>
> That's why Philips makes high temperature caps rated for 125'C use.
> Better Tc, not just longer life at high temperature.


** More Bunkum.



.......... Phil

 

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Phil Allison <philallison@tpg.com.au> wrote:
>"Scott Dorsey"
>> Phil Allison <
>> >
>> > BTW Can you verify ( for Arny's benefit) that heating an electro
>reduces
>> >the ESR reading ?
>> >
>> > Using a hot air gun on a cap ( say 47 uF, 350 volt) while connected to
>the
>> >meter.
>>
>> Sure it does.
>
> ** By what ratio though ???
>
> I see about a 5:1 reduction.

Between what and what? What case temperature do you start seeing it drop
at and how far up does it go before it drops 5:1?

Most chemical reactions are faster at higher temperatures. Electrolytic
effects are no exception. Unfortunately the reactions that cause capacitors
to fail also are faster.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

 

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"Scott Dorsey" <kludge@panix.com> wrote in message
news:cgbmdb$s4j$1@panix2.panix.com...
> Phil Allison <philallison@tpg.com.au> wrote:
> >"Scott Dorsey"
> >> Phil Allison <
> >> >
> >> > BTW Can you verify ( for Arny's benefit) that heating an electro
> >reduces
> >> >the ESR reading ?
> >> >
> >> > Using a hot air gun on a cap ( say 47 uF, 350 volt) while connected
to
> >the
> >> >meter.
> >>
> >> Sure it does.
> >
> > ** By what ratio though ???
> >
> > I see about a 5:1 reduction.
>
> Between what and what?


** Room temp and hot.


> What case temperature do you start seeing it drop
> at and how far up does it go before it drops 5:1?


** That is what YOU are being asked to try, see and verify.

If the cap is an 85C type then go to 85 C.

If a 105 C then go to 105.


(snip even more absurd drivel )




.............. Phil

 

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Phil Allison <philallison@tpg.com.au> wrote:
>"Scott Dorsey" <kludge@panix.com> wrote in message
>> >
>> > ** By what ratio though ???
>> >
>> > I see about a 5:1 reduction.
>>
>> Between what and what?
>
> ** Room temp and hot.

How hot is that hot, though? That's my question.

>> What case temperature do you start seeing it drop
>> at and how far up does it go before it drops 5:1?
>
>
> ** That is what YOU are being asked to try, see and verify.
>
> If the cap is an 85C type then go to 85 C.
>
> If a 105 C then go to 105.

Ahh, okay, to rated temperature. Why didn't you just say that?
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."