Groups > sci.electronics.design > #446171

Re: OT: in favour of gradualism

From	Don Y <blockedofcourse@foo.invalid>
Newsgroups	sci.electronics.design
Subject	Re: OT: in favour of gradualism
Date	2017-02-04 15:44 -0700
Organization	A noiseless patient Spider
Message-ID	<o75lda$oa3$1@dont-email.me> (permalink)
References	(4 earlier) <o75a8v$hia$1@dont-email.me> <efmqjcFe61gU1@mid.individual.net> <o75g67$6t9$1@dont-email.me> <tqjc9ct91aa4dopd9rvu2d96j16ss8loug@4ax.com> <o75kqt$mb4$1@dont-email.me>

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On 2/4/2017 3:35 PM, tom wrote:

>>> You spec a 2000hr part in a power supply.  It meets the design
>>> specifications.
>>> It meets the expected lifespan of the product (e.g., clears warranty).
>>> But, realistically, you KNOW that this will result in the $200 product being
>>> shit-canned in 2-3 years (of normal use).
>>
>> A typical aluminum electrolytic cap will have a rated lifetime of 2000
>> hours, and a shelf life the same. That's 80 days, totally insane. Does
>> Digikey stock them for hours, like dougnnuts? They actually work for
>> decades.
>
> That is at the rated temperature. 85 or 105 °C

And operating voltage (though you usually can't get more than a 2X increase in
life by operating at a reduced voltage).

So, caps sitting on a shelf in a warehouse at "STP" have life expectancies
~500 times greater than when operating at ~100C *internal* temperatures.
2000 hours becomes 100 years in storage.

(realistically, seals degrade after 10-20 years)

Thread

OT: in favour of gradualism bill.sloman@ieee.org - 2017-02-03 03:39 -0800
  Re: OT: in favour of gradualism Winfield Hill <hill@rowland.harvard.edu> - 2017-02-03 04:21 -0800
    Re: OT: in favour of gradualism bill.sloman@ieee.org - 2017-02-03 04:57 -0800
      Re: OT: in favour of gradualism Jon Elson <elson@pico-systems.com> - 2017-02-03 11:38 -0600
        Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-04 07:21 -0800
          Re: OT: in favour of gradualism krw@notreal.com - 2017-02-04 10:42 -0500
            Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-04 08:15 -0800
              Re: OT: in favour of gradualism krw@notreal.com - 2017-02-04 11:36 -0500
                Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-04 09:40 -0800
                Re: OT: in favour of gradualism krw@notreal.com - 2017-02-04 13:52 -0500
                Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-04 11:50 -0800
                Re: OT: in favour of gradualism krw@notreal.com - 2017-02-04 20:31 -0500
            Re: OT: in favour of gradualism Jon Elson <elson@pico-systems.com> - 2017-02-04 18:04 -0600
              Re: OT: in favour of gradualism krw@notreal.com - 2017-02-04 20:33 -0500
    Re: OT: in favour of gradualism jurb6006@gmail.com - 2017-02-03 05:00 -0800
      Re: OT: in favour of gradualism bill.sloman@ieee.org - 2017-02-03 09:03 -0800
    Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-03 09:35 -0700
      Re: OT: in favour of gradualism bill.sloman@ieee.org - 2017-02-03 09:10 -0800
      Re: OT: in favour of gradualism tabbypurr@gmail.com - 2017-02-03 17:18 -0800
      Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-04 07:24 -0800
        Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 12:34 -0700
          Re: OT: in favour of gradualism tabbypurr@gmail.com - 2017-02-04 12:04 -0800
          Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-04 12:07 -0800
            Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 14:15 -0700
              Re: OT: in favour of gradualism John Larkin <jjlarkin@highlandtechnology.com> - 2017-02-04 14:02 -0800
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 15:19 -0700
                Re: OT: in favour of gradualism "tom" <tmiller11147@verizon.net> - 2017-02-04 17:36 -0500
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 15:46 -0700
                Re: OT: in favour of gradualism Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-04 14:56 -0800
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 16:17 -0700
                Re: OT: in favour of gradualism "tom" <tmiller11147@verizon.net> - 2017-02-04 18:22 -0500
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 16:55 -0700
                Re: OT: in favour of gradualism John Robertson <spam@flippers.com> - 2017-02-04 18:22 -0800
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 21:26 -0700
                Re: OT: in favour of gradualism "tom" <tmiller11147@verizon.net> - 2017-02-04 17:35 -0500
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 15:44 -0700
                Re: OT: in favour of gradualism "dcaster@krl.org" <dcaster@krl.org> - 2017-02-04 17:42 -0800
                Re: OT: in favour of gradualism krw@notreal.com - 2017-02-04 20:56 -0500
              Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-05 08:14 -0800
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-05 11:56 -0700
                Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-06 14:35 -0800
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-06 16:43 -0700
                Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-06 17:12 -0800
                Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-06 18:59 -0700
                Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-07 07:40 -0800
                Re: OT: in favour of gradualism tabbypurr@gmail.com - 2017-02-07 12:16 -0800
                Re: OT: in favour of gradualism krw@notreal.com - 2017-02-06 21:11 -0500
                Re: OT: in favour of gradualism tabbypurr@gmail.com - 2017-02-05 12:43 -0800
          Re: OT: in favour of gradualism krw@notreal.com - 2017-02-04 20:42 -0500
      Re: OT: in favour of gradualism John Larkin <jjlarkin@highlandtechnology.com> - 2017-02-04 10:05 -0800
        Re: OT: in favour of gradualism Joerg <news@analogconsultants.com> - 2017-02-04 10:24 -0800
        Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 12:45 -0700
          Re: OT: in favour of gradualism "dcaster@krl.org" <dcaster@krl.org> - 2017-02-04 17:54 -0800
            Re: OT: in favour of gradualism Don Y <blockedofcourse@foo.invalid> - 2017-02-04 21:45 -0700

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