That is the reason I said using an 85C electrolytic cap as an output cap for a switching power supply is engineering malpractice.
Well, I wouldn't say it's a malpractice, but you certainly have to know what you are doing if you are using general purpose caps for a switching power supply. Take for example CRT monitors and TVs - a lot of them use general purpose caps in their power supplies. Yet, many of them lasted 10 years or more - even the ones with dodgy cap brands. A lot of my CRTs are actually close to 20 years old now and still function properly. I've pulled caps from a few just for fun, and they tested within specs too. So again, if the designed of the device know what they are doing, they can get away with general purpose caps. But for most things built nowadays, I wouldn't count on it.
Yes, even good CRT monitor use generic capacitors on the secondary of the switching power supply section.
For example a pair of Samxon GS which have very relaxed specifications. They still measures correctly. Replaced them with low E.S.R. counterparts though.
Some CRTs from the 2000s have Elite, they fail in the secondary and develop high E.S.R. on the B+ rail (without failing).
However, their WF series is known to have a lot of problems, particularly with being heat-sensitive and going bad very quickly if not used. All in all, the failure mode is very similar to United Chemicon KZG.
So avoid Sanyo WF series.
WG is OK.
WX and SE if I recall are OK as well.
Also, I think Sanyo now makes caps under the Suncon name, so if you see any new Sanyo caps (especially from cheap sites like eBay, Amazon, AliExpress, and etc.), beware that they could be counterfeit.
Yeah, the spambot that made the 1st post with that half-baked cap list looked iffy to me right from the beginning, but there was nothing wrong with it that I could flag it for. Generally, though, whenever I see a new user post some irrelevant garbage in an old sticky thread, I don't reply and only monitor that user, as chances are it's a spam bot. Sure enough when that spam bot made the 2nd post, it contained garbage spam links.
Wow! ^
Talk about small caps hidden in big cans.
What capacitance did it measure?
If it measured 4700 uF, I bet it probably was a lower voltage cap then (like maybe 25V or 35V?)
On the plus side, all of that empty space inside the can could allow a lot of gas to build up when the cap starts failing.
If you have more of these caps, it would certainly be interesting to subject them to more tests to see how/what they do over time (like maybe install in some inexpensive equipment and abuse the crap out of them, if that's possible.)
TV-s are usually not that hot and the components are not that cramped. Especially the CRT TV-s. For computer PSU-s I always use 105C caps.
Useful conversions. I don't "speak" imperial. Please use metric, if you want to address me.
1km=1000m=100000cm, 1inch=2.54cm, 1mile=1609.344meters, 1ft=30.48cm 1gal(US)=3.785liters, 1lb=453grams, 1oz=28.34grams
NCC TMV - another bad series from NCC, same as KZG, but these, mostly 680uf 4v, don't have vent on top, so they bulge on bottom, put 4-5 out from an 775 Asus board, they were bulged on bottom.
Cheap Chinese store that sells all kinds of cheap electronics junk typically will also sell same type of capacitors.
While the photos in that store show Sanyo caps, note that there is nothing in the description that says you will get Sanyo caps. And looking at the reviews, I see a lot of people showcasing Chong/ChengX caps with measurements on their cheapo ESR meters - as if that has any meaning at all.
The problem with cheap caps is not only that they may not measure in spec (in fact, you were probably unlucky, because cheap caps usually DO measure in spec), but that they likely won't last any reasonable time. They are "good" for a cheap, temporary repair. And how long that "temporary" can go on, no one can tell, because cheap caps are just so inconsistent. They could last for years... or more than likely, they will just last a few months and go bad, especially if they are used in any kind of stressful application.
If you do want to buy caps online from AliExpress or eBay, the key is to look what else the seller has in their store. If they seem to sell only caps and/or NOS electronic components, they actually might have genuine branded capacitors. But if they don't... I pass. You're better off reusing caps from old TVs than use these cheap caps.
Caps labeled FOAI FZL 470uf 6.3v and 25v in a Motorola SB6141 cable modem bought in 2015. Started having T3 errors.
just opened it yesterday and found this:
I replaced all the swollen and non swollen FOAI caps and it seems to be working better now.
"...off the record, unnamed government sources
alluded to unsubstantiated innuendos about
alleged indiscretions and insinuated that they
are rumored not to be without basis for further
speculation..."
Yep, those caps are preggers and not going to deliver anything good. FWIW, the date on the PWA is February 2012.
PeteS in CA
Power Supplies should be boring: No loud noises, no bright flashes, and no bad smells.
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To kill personal responsibility, initiative or success, punish it by taxing it. To encourage irresponsibility, improvidence, dependence and failure, reward it by subsidizing it.
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Came across these two recently, CepXon, and CajoXen, both sound like CapXon knockoffs. It's hard to imagine these being any worse than the brand they're knocking off.
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