Popping capacitors Who has post 2006 hardware with bad caps?

Its maybe not the caps fault, maybe its a design fault ? Maybe someone has put in wrong voltage cap ? Maybe it cant cope with current surge at power up or later?

Me, just about every day of my working life ...

Arfa

CheetahHugger hath wroth:

Hmmm.... I have a fairly new Samsung Syncmaster (something) 19" LCD on the bench with exactly the same problem. I'll start on it on Weds and see what I find.

I'm not sure of the manufacturing date, but I've been seeing them in new +5/+12v external switching power supplies used on external USB to hard disk enclosures. I have a few torn apart and all have volcanic electrolytics.

I haven't seen any recently in the usual places (motherboards, power supplies, and consumer electronics). I found a few in LCD panel power supplies, but they were much older than 2006. To find them, ESR meter, optical pyrometer, IR thermometer, or a really nifty IR thermography scanner that I borrow ocassionaly. I've tried using various digital cameras for IR and had no luck.

--
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

There is probably some other common fault that is causing the caps to be over stressed, or there is a design fault.

Investigate things such as the working temperature of the supply, and if there is adequate air flow through it. Also, check the voltage across the cap while the supply is operating.

For an experiment use a higher voltage rated cap and see what happens. If you can squeeze a 25V cap in its place, or find a way to use 2 X 470 uF /

25V in parallel to replace if there is no space for a single at 1000 uF. Also, make sure that the cap's temperature is rated at 105 deg Cels.

--

JANA _____

1000uf 16v popped, as these were made in 2006 i am suprised, that was a problem of the past or are there more people here that still have trouble with capacitors? Someone gave me 2 tft monitors which briefly show picture and then shut off, i open those tomorrow and see if they also have bad capacitors. I am aware of the motherboard capacitor problem but that too doesn't happen anymore or does it? Who sees post 2006 hardware with bad caps?

Cheetah

Any particulat brands ?

Graham

Were there never any 105C 'bad caps' ?

Graham

Yes, i can, it's just that i remember huge problems with capacitors about 10 years ago and it seems it's still a common failure making me think it's a weak component purposely installed to make sure the appliance in question will only just outlast the warranty. To me this is theft from consumers.

Cheetah

On my last 2 TFT monitors teapo and jackcon, on the power supplies it's tah-ken and fuhjyyu (fake fujitsu?). This is on Nec, Asus and Powermaxx power supplies from which i have 7 with the same cap popped. This does look like a design fault so i will put a higher voltage cap in .

Cheetah

Nope. The two main things that they always have in common, are that they are either secondary side filter caps on switchers, or located right next to a component that runs hot. SMPS designers seem to have something programmed into their genes, which compels them to do this ...

Arfa

LOL ! I had a similar problem with a layout guy. He loved to crowd all the hot items together. In one case we even found that a certain power diode would after extended operation virtually 'weld' itself into the tiny PTH he'd provided it with.

Graham

capacitors

making me

the

i think you need to factor in the product value and penny counters as well, Cheapo mother boards were big problem once upon a time. The mother board and other electronic mfgs are ordering thousands and millions of components and a couple of fractions of pennies here and there really adds up to big savings or profit for them. I replaced some buldging caps in my old cheapie MOBO with nichicon equivalents and the board still runs great.

That said, there was a genuine issue a few years back where one (or more ??) of the major electrolytic manufacturers had a batch of 'fake' electrolyte swung across them, which resulted in hundreds of thousands of substandard caps appearing on the market, and finding their way onto computer motherboards, and failing after a relatively short period of time. Obviously, the mo-bo manufacturers thought that they were buying full spec caps, and the cap manufacturers thought that's what they were selling, so not a penny-pinching situation in that case.

Arfa

IIRC Abit was one mobo manufacture that got bit by bad caps.

Yes. Still not sure if it was that or a dodgy PSU of the same era that gave me trouble.

Graham

I have one of those Abits. I tried to replace them but the local elctronics dealer(central Canada) wanted $40.00 for 20 caps. (I could replace the MoBo for that price, its outdated anyway and I just wanted to try replacing the caps for the heck of it). I am waiting to find a more reasonable seller with decent prices.

-- to reply remove STOP from email addy

Yeah,

But i am currently looking over a pile of scrapped items i took from a local computer shop, including about 50 power supplies and 2 tft monitors, and several complete computers fairly late, amd athlon mainly, who have all in common that they are discarded because of bad caps. The problem the previous poster mentioned is true here as well, they want up to 1 euro for just 1 capacitor, so i solve that by salvaging dead mainboards for their caps to replace the bulged ones. Unless someone knows a good supplier for 105° caps suitable for computer who has no objection to ship to or is located in europe. Any suggestions, i would like 1000 or such of each common number.

Cheetah

Rapid Electronics

I believe that they will ship to mainland Europe

Ron(UK)

I bought a bag of 30 1500 µF 6.3V nichicon 105° caps from China on Ebay. The caps were $10.99 and shipping to Sweden $5.99.

Here is one such auction:

They shipped quickly, ~1 week, and the price is very reasonable.

I have no affiliation with them, other than I'm a happy customer.

I have also bought LED:s from another chinese vendor, and I'm very happy with these as well.

Thanks for the info. Sounds like reasonable prices. I will give them a call.

regards hg

Thomas Tornblom wrote:

-- to reply remove STOP from email addy