647-UHM0J102MPD3 Nichicon 6.3v 1000uf from Mouser swiftly bad

[mrmazda]

Tiny as these and the text on them is, even with magnification, I doubt whether I would be able to tell whether they are genuine.

I bought 10 in July of 2008, 10 more June of 2011, and 40 early last month. IIRC (far from guaranteed), when the newest arrived I mixed them with the remainder, then installed 17 in an Asrock K7Upgrade-880. 23 new remain in the bag.

Several days ago the Asrock was still working. Today it will not POST. 9 of the new caps are no longer flat on top already. 2 between CPU socket and rear panel ports are oozing yellow.

[kc8adu]

Re: 647-UHM0J102MPD3 Nichicon 6.3v 1000uf from Mouser swiftly bad

you probably installed them backwards.
asrock/asus marks them backwards.

[mrmazda]

Re: 647-UHM0J102MPD3 Nichicon 6.3v 1000uf from Mouser swiftly bad

Yikes! Are there manufacturers of other products setting this n00by trap? Posting and running normally with 18 of them installed backwards I find hard to believe. Uptime functioning properly since their replacement was surely more than 10 hours, maybe twice that. Yet, replacing all again but with polarity reversed WRT labels like those I did not change, it's running again. Is reversed polarity responsible for the swelling, or could I have gotten a bad batch?

[mariushm]

Re: 647-UHM0J102MPD3 Nichicon 6.3v 1000uf from Mouser swiftly bad

Reverse polarity is definitely a cause for them swelling... you're lucky they lasted that long and didn't just pop their tops.

[Heihachi_73]

Re: 647-UHM0J102MPD3 Nichicon 6.3v 1000uf from Mouser swiftly bad

Nichicon quality. If it was cheap junk from RadioShack (Australian equivalent is Jaycar) they would have been lucky to last 2 minutes.

I will confirm, my ASRock N68-S3 board has "reversed" markings - its original caps have the negative stripe on the non-shaded side.

[PeteS in CA]

Re: 647-UHM0J102MPD3 Nichicon 6.3v 1000uf from Mouser swiftly bad

Indeed, H_73! Reverse-installed electrolytics tend to be noisy, messy, and often they launch. When I worked at Boschert (a 70s-80s P/S company) the ceiling tile above what had been the manufacturing test area had lots of circular holes, some with caps still embedded. Also while I was at Boschert, a guy working at the bench next to mine applied 48V to a board in which the assembler had accidentally installed a 7.5V part (same size and color). The cap launched and hit him in the chest. He wasn't hurt, but I didn't see him in the lab for the net hour or so.