Capacitors brands   - Page 1
Forum section: electronics / projects

author: electronics technician
author_rank: Regular Contributor
timestamp: March 20, 2014, 04:05:00 am
content: Im looking for a 100 or more volts high capacitance capacitor but dont know if the brand is any goodany advice is welcomeNOTE the voltage has to be at least 100v, above 100v even better that gives me more of a safety margini am in process of making an audio amplifier that needs 80v running voltagei tested the same amp with 48v-0-48v two 65v caps in series and 2 50v caps in series all 3300uf (microfarads) and 1 of the 65v caps got very hot and burst not violently btw luckly i fused the input voltage fuse blew outso low ESR or not thanksi checked ebay and here is what i foundhttp://www.ebay.com/itm/Nippon-Chemi-Con-82000uF-100V-Capacitor-0416L-82-000uF-/270642127384?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item3f03872218this particular cap makes me smile because of the capacitance

author: Fsck
author_rank: Super Contributor
timestamp: March 20, 2014, 04:23:00 am
content: Chemi Con's one of the best. high voltage + high capacitance usually = giant size.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 20, 2014, 04:30:09 am
content: thanks for the quick reply i will do some researchDoes it have any other brands to compare

author: Fsck
author_rank: Super Contributor
timestamp: March 20, 2014, 04:41:59 am
content: Rubycon, Panasonic, Sanyo, Elna, Illinois Capacitor, Vishay, Cornell Dubilier, series dependent Nichicon

author: electronics technician
author_rank: Regular Contributor
timestamp: March 20, 2014, 04:43:16 am
content: thank you very much i will research and compare

author: Kjelt
author_rank: Super Contributor
timestamp: March 20, 2014, 08:25:47 am
content: Just as a side notice, you do know that if you put to capacitors in series you need to balance them? Mostly with high ohm resistor network across them, other wise one of the elco's could get more voltage then the other and overvoltage could cause you're experience even with new good brand electrolytes. But you probably know that.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 20, 2014, 12:33:26 pm
content: Quote from: Kjelt on March 20, 2014, 08:25:47 amI didnt know that?how do you balanc them? i think thats what caused it thenis there a formulathanks for that important inputthat means i could have saved that cap

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: March 20, 2014, 01:11:50 pm
content: Balancing is a good idea, plus the resistors will act as discharge resistors. OTOH, with increasing voltage the leakage current goes up, so most supplies are self balancing. That's probably not why your cap blew up. One was almost certainly installed backwards or there was a rectifier problem.

author: TMM
author_rank: Frequent Contributor
timestamp: March 20, 2014, 02:00:18 pm
content: Quote from: electronics technician on March 20, 2014, 12:33:26 pmSee page 13:http://www.coilgun.info/theorycapacitors/AEappGUIDE.pdfAdditionally, if the caps are exceptionally leaky then you must ensure that the balancing resistors have a lower resistance than the leakage resistance.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 20, 2014, 02:37:46 pm
content: Quote from: Conrad Hoffman on March 20, 2014, 01:11:50 pmthats funny because i was getting dcv out but i put 2 65v together in parallel and the 2 50v caps in parallel then put them in series with the 65v its the exact same as this ps below the only things that are different is the voltage whcih was 46-0-46vac before rectification after it was 42-0-42dc before capsQuote from: TMM on March 20, 2014, 02:00:18 pmthanks i will check it out before i go play with the ps again

author: electronics technician
author_rank: Regular Contributor
timestamp: March 20, 2014, 02:43:43 pm
content: will a short somewhere on the ps or amplifier cause the cap to blow?

author: zaoka
author_rank: Frequent Contributor
timestamp: March 21, 2014, 01:58:19 pm
content: Quote from: Fsck on March 20, 2014, 04:41:59 amDont forget Hitachi

author: dannyf
author_rank: Super Contributor
timestamp: March 21, 2014, 05:38:04 pm
content: QuoteChemi con is a great brand.When sold on ebay, it is a better brand if you want to get a fake capacitor.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 21, 2014, 07:24:00 pm
content: Quote from: dannyf on March 21, 2014, 05:38:04 pmwhat do you mean when sold on ebay? it is a better brand if you want to get a fake capacitor.

author: SeanB
author_rank: Super Contributor
timestamp: March 21, 2014, 07:26:35 pm
content: Many outright fakes and close knock offs. Cheni con, Ckemi con, Cheha con........... All fakes with printing designed to look almost like the real thing. Most might pass basic testing when new, but not after any use or aging.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 21, 2014, 07:41:04 pm
content: thanks i will be sure to remember that

author: krish2487
author_rank: Frequent Contributor
timestamp: March 21, 2014, 07:52:45 pm
content: Just 1.Others have covered the important brands.I have more of a statutory warning,Avoid ebay.Get the same capacitors from digikey or farnell.You basically dont save anything if you buy from ebay vis-a-vis digikey.Just remember, if it is too good to be true, then it probably is.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 21, 2014, 07:55:41 pm
content: ok thanks

author: electronics technician
author_rank: Regular Contributor
timestamp: March 22, 2014, 01:31:58 am
content: Quote from: SeanB on March 21, 2014, 07:26:35 pmits chemi-con on e-bay i checked the spelling but thats true it could be old stock

author: Fsck
author_rank: Super Contributor
timestamp: March 22, 2014, 01:43:29 am
content: Quote from: electronics technician on March 22, 2014, 01:31:58 amproblem is, even if spelled correctly, chance of fakes is extremely high.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 22, 2014, 02:07:44 am
content: i will take everyone's advice into consideration and check digikey or farnell for what i need