On Jan 17, 2006, at 8:53 AM, Steve Thompson wrote:
>
>
> dick.knol@planet.nl wrote:
>> Rich Measures AG6K sells 450 WV 105ºC electrolytic caps for HT PSU
>> use.
>> (http://www.somis.org/Price-Info.html)
>>
>> Please note that contrary to crack, a 105ºC rating electrolytic cap
>> cannot be obtained on every street corner. However, the 105ºC rating
>> will result in a much longer servbice life in a hot HFF power amp
>> environment.
> A while ago I looked at the ratings on Philips electrolytics, where you
> can get physically identical capacitors, one family with 85C rating,
> the
> other with 105C rating. For the same value, the ripple current ratings
> were different, as were the lifetimes at the operating temperatures.
>
> I worked out the thermal resistance from the maximum allowed
> temperature
> and I^R rating at 85C. Working backwards to 105C, I ended up with
> exactly the ripple current specified for the 105C part. The different
> lifetimes were related in just the same way. In other words, these
> appeared to be absolutely indentical, just specified at different
> operating temperatures. I don't know if there's any manufacturing
> difference between 105 and 85C parts - but it would not surprise me if
> they all come off the same conveyor and just had different part numbers
> printed on them.
The Matsushita low-ESR, high-ripple-I, 105º units we stock weigh in at
about 80% more than similar-volume older 85ºC aluminum electrolytics.
They are 3mm dia. by 50mm long and they weigh 90.2 grams
>
> I've not tried it for other brands but I can imagine the same might
> apply.
>
> Steve
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
Richard L. Measures, AG6K, 805.386.3734. www.somis.org
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|