Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

caps and lifespan
caps and lifespan
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 14th December 2010, 06:08 PM   #1
Salomonander is offline Salomonander  Germany
diyAudio Member
Join Date: Dec 2010
Default caps and lifespan


this is my first post here. im rather new to electronics so i guess this is a newbie thread. im about to order capacitors in order to recap my mixing desk. its a very nice all discrete desk, so i want to get high quality caps. i did some research and it seams to come down to either nichicon kz, elna Silmic or panasonic fm. now my big question is lifespan. the panasonic last a lot longer telling from the datasheet. the nichicons and elnas only last 1000 hours...what does this mean in real life?
my desk is running all day...everyday. does this mean the nichicons and elnas will go bad after a little over a year? i must be getting something wrong....the caps that are in there now are at least 15 years old...still working. id appreciate if someone could give me some advice. thanks a lot.
  Reply With Quote
Old 14th December 2010, 09:15 PM   #2
indianajo is offline indianajo  United States
diyAudio Member
indianajo's Avatar
Join Date: Jan 2010
Location: Jeffersonville, Indiana USA
Default predicted capacitor life

Nichicon, for example, sells both 1000 hour and 5000 hour caps in the 470 uf 50 V size. Newark.com has both. The 1000 hour is $.91, the 5000 hour is $1.84.Here is the 5000 hour link http://www.newark.com/nichicon/upm1h...ial/dp/65R3633 . As I am not selling into a competitive market where first cost is king, I tend to buy 2000 hour up electrolytic capacitors so I don't have to replace it again next year. I don't run competitive trials, and I don't know of a consumer digest of electronics parts. I do know I bought a competitively priced HDTV converter from a big box retailer, and the caps were bad the day I bought it. It has diagonal lines (60 hz) in the signal that go away after 10 minutes. I would guess the 5000 hour cap has more expensive materials or better final assembly testing than the competing cap from the same manufacturer. I like newark because they highlight the hours life right in the selector table, so you can filter out the garbage without wasting time. In europe they are farnell.co.uk.
Some posters on this board are married to some series of cap like it was a religion or something. I'm more into numbers. ESR can be important,self inductance and life can be important, copper leads instead of steel can be important to reduce frequency cold joints hand soldering. You have found a Nichicon "competitive" series, apparently. Nichicon also has caps installed in Siemens premium brand 460 V 3 phase motor drives, where temperature is extreme and customers buy enough ot the same device to remember if they are changing it out more than average. The nichicons are not a big cause of failures there, but I would suspect they are not the cheap ones. I've seen a couple of nichicons blown up after 15 years high temp 5 days a week 24 hours/ day service. So the brand is not as important as the series the buyer chooses. I've got both blown up Siemens motor drives, and Semi drives. The Semi brand drives tended to leak slime into their enclosures at about 4-5 years, then refuse to power up on a cold morning. I spent a lot of Sunday nights rewiring machines that had Semi drives for something else, because Semi drive was bankrupt. Siemens drives do not have the 5 year leaky caps problem. Semi drives did not use nichicon.
Dynakit ST70, ST120, PAS2,Hammond H182(2 ea),H112,A100,10-82TC,Peavey CS800S,1.3K, SP2-XT's, T-300 HF Proj's, Steinway console, Herald RA88a mixer, Wurlitzer 4500, 4300

Last edited by indianajo; 14th December 2010 at 09:37 PM.
  Reply With Quote
Old 14th December 2010, 09:43 PM   #3
Steerpike is offline Steerpike
diyAudio Member
Steerpike's Avatar
Join Date: Jan 2006
Location: Johannesburg, South Africa
Those lifetime figures can be confusing. Usually they are the guaranteed life at the maximum operating temperature, 85C or 105C. At more normal temperatures (i.e., in well ventillated and well designed equipment, rather than cheap far-east plastic stuff) they will be at little more than room temperatue all their life and will last considerably longer.

5000h life also doesn't mean they will die at hour 5001; it does mean that they are no longer expected to be within their rated tolerance (+10% / -5% or whatever it is). Your old caps are still working but they may have dropped in value to say 50% or 60% of their correct value. In good designs, they are way over-rated so the anticipated change in value is accounted for and shows few problems.
Steerpike's Toybox

Last edited by Steerpike; 14th December 2010 at 09:46 PM.
  Reply With Quote
Old 14th December 2010, 11:02 PM   #4
jcx is offline jcx  United States
diyAudio Member
Join Date: Feb 2003
Location: ..
Default buy a high temp rated cap and keep it cool


and buying larger V rating helps a little on life too

any signal coupling electros should be Al, non/bi-polar, with high V overating factor - even if they have bias V - see Bateman's "Capacitor Sound" results - the old "back-to-back" polar configuration didn't give as low measured distortion as non/bi-polars with full thickness oxide grown on both foils

also technology evolution allows more C in the same case size - another plus for signal coupling distortion minimization

of course even the worst film was better than the best electrolytic

Last edited by jcx; 14th December 2010 at 11:10 PM.
  Reply With Quote
Old 14th December 2010, 11:20 PM   #5
kevinkr is offline kevinkr  United States
diyAudio Moderator
kevinkr's Avatar
Join Date: Sep 2004
Location: Boston, Massachusetts
caps and lifespan
The biggest bang for the buck lifetime wise is to buy caps rated for 105 degree C.

Note that for every 10 C reduction in internal temperature the capacitor life doubles. In cases where there is no ripple current this is the prevailing ambient temperature around the cap. In the case where ripple current is present the internal temperature may be appreciably higher than ambient. It pays to look for low ESR types with the highest ripple current ratings you can find for these applications. (Input filters in linear supplies for example.)
"To argue with a person who has renounced the use of reason is like administering medicine to the dead." - Thomas Paine
  Reply With Quote


caps and lifespanHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Capacitor lifespan and audio quality KHashmi316 Parts 47 28th September 2012 05:00 AM
Lifespan of capacitors GeeVee Parts 9 2nd February 2011 08:15 PM
0ne 100uF cap or ten 10uF caps (or two 200uF caps...etc) Hubba Power Supplies 3 15th September 2010 06:13 PM
6SN7 plate voltage, current and lifespan cbutterworth Tubes / Valves 1 25th October 2007 08:25 PM
Lifespan of old oil caps grataku Parts 18 15th September 2003 07:17 AM

New To Site? Need Help?

All times are GMT. The time now is 06:57 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio