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-   -   The Hall of Shame - Badcaps Photo Montage (https://www.badcaps.net/forum/showthread.php?t=424)

momaka 01-06-2022 07:50 PM

Re: The Hall of Shame - Nichicon HZ series with H05xx date codes
 
Quote:

Originally Posted by Uranium-235 (Post 1096671)
Those XFX 7000/8000 cards almost ALWAYS had bad caps. I had next door neighbor over a decade ago with three of them

Yeah, XFX really liked to use those crappy GSC/Evercon/Sacon caps on many (but not all) of their 6000, 7000, and 8000 series of cards. In the case of the bad Nichicon HZ I showed, though - that was a "recycled" cap I scavenged from a dead Xbox 360 motherboard. The whole point was to note that 2005-made Nichicon HZ are fairly unstable and like to go bad, but 2006 and newer aren't (at least not yet. :hiding: )

RJARRRPCGP 01-06-2022 08:36 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
"SI" cap, IIRC:

https://www.badcaps.net/forum/showpo...postcount=3149

UglyBetty 01-08-2022 02:00 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
5 Attachment(s)
Okay, here is my contribution. A few years ago I used a Motorola power supply that was from a retires base-station police band radio. I used it to build a 20amp power supply to run some of my radio gear.
I walked into the shack one day and I could smell something burning. I looked around but did not really see anything. No visible smoke. I noticed this power supply was off. I could tell this was where the stink was emanating from. I just took it out of service, set it aside and used another power supply.
I pulled it out and removed the cover today and this is what I found. It about burned my shack down. If it was not inside a metal case I built it might have!! Enjoy!

PeteS in CA 01-09-2022 08:20 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
Look like the cause was something other than the caps. I think Nichicon discontinued the PL series something like 15 years ago, so they had a pretty long life.

momaka 01-09-2022 10:52 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
Quote:

Originally Posted by PeteS in CA (Post 1097551)
Look like the cause was something other than the caps. I think Nichicon discontinued the PL series something like 15 years ago, so they had a pretty long life.

Concur.

Actually, I do have a theory of what might have happened there. Being that old, those Nichicon probably had deteriorated rubber seals at such age. If at some point the PSU was "bumped" or exposed to slightly stronger vibration, that could have caused some electrolyte to leak out. Moreover, the PL series are somewhat similar to the PR series of that age in that they both used the quaternary ammonium salt in their electrolyte. Now, the PR series were actually pretty well-known for leaking electrolyte from their bungs after a number of years. PL, on the other hand, not anywhere near as often.

So basically, I'm speculating here that these Nichicon PL caps started to leak a little bit of electrolyte on the PCB. Since electrolyte is quite corrosive, it probably started eating traces away. Over time, it could have caused a weak or bad connection somewhere. On top of that, electrolyte is also conductive and flammable too. So if you have a weak connection and you add a conductive agent to it (possible source of spark or heat generation) that's also flammable... I think that might explain how the small inferno happened inside the PSU. Or does that sound like a big tinfoil hat theory? :foilhat:

And in any case, the big question is: why didn't the PSU's protection circuitry shut it down?
All in all, that PSU doesn't look like a cheapo no-name dubious brand. But perhaps it just lacks/lacked modern protections (aside from maybe complete short-circuit)?

SwedishDiesel 02-23-2022 03:41 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
9 Attachment(s)
Kaboomf.

Nichicon HM caps from the Optiplex I'm fixing. Don't mind the odd camera angles.

PeteS in CA 02-23-2022 06:08 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
The caps are over 19 years old, was the MB in use the whole time?

SwedishDiesel 02-23-2022 06:56 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
I'm not sure, but I believe it was taken out of service many years ago. I don't have much info on it but if I had to guess it was put into storage after it blew a cap or two.

Heihachi_73 02-25-2022 01:30 AM

Re: The Hall of Shame - Badcaps Photo Montage
 
HMs (and HNs) from the early 2000s are known to be flaky. 2005 and later are usually fine, as are 1990s.

SwedishDiesel 02-25-2022 10:30 AM

Re: The Hall of Shame - Badcaps Photo Montage
 
Yeh, this PC is from 2002 so it's within the bad caps era for that series.

RJARRRPCGP 02-25-2022 07:25 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
Quote:

Originally Posted by SwedishDiesel (Post 1112436)
Yeh, this PC is from 2002 so it's within the bad caps era for that series.

Yep, can confirm 2002 on the caps.

kc8adu 02-28-2022 03:46 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
Motorola quantar repeater supplies burn up just like that.
And its leaking electrolyte that set it off.
I recap them on sight.
Just did one for a uhf p25 system i am putting on the air.

Quote:

Originally Posted by momaka (Post 1097564)
Concur.

Actually, I do have a theory of what might have happened there. Being that old, those Nichicon probably had deteriorated rubber seals at such age. If at some point the PSU was "bumped" or exposed to slightly stronger vibration, that could have caused some electrolyte to leak out. Moreover, the PL series are somewhat similar to the PR series of that age in that they both used the quaternary ammonium salt in their electrolyte. Now, the PR series were actually pretty well-known for leaking electrolyte from their bungs after a number of years. PL, on the other hand, not anywhere near as often.

So basically, I'm speculating here that these Nichicon PL caps started to leak a little bit of electrolyte on the PCB. Since electrolyte is quite corrosive, it probably started eating traces away. Over time, it could have caused a weak or bad connection somewhere. On top of that, electrolyte is also conductive and flammable too. So if you have a weak connection and you add a conductive agent to it (possible source of spark or heat generation) that's also flammable... I think that might explain how the small inferno happened inside the PSU. Or does that sound like a big tinfoil hat theory? :foilhat:

And in any case, the big question is: why didn't the PSU's protection circuitry shut it down?
All in all, that PSU doesn't look like a cheapo no-name dubious brand. But perhaps it just lacks/lacked modern protections (aside from maybe complete short-circuit)?


ReeceyBurger123 03-08-2022 12:57 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
4 Attachment(s)
Some caps for you guys:

Pic 1: Cambridge Audio 15,000uf 63v causing dc error suspect voltage collapses because of these…..

Pic 2: Nichicons out of a Bose thing causing no power, all SMD caps had to be replaced in the device too as you can see.

Pic 3: Enercon capacitors out of a H&K mass thing, whole lot of supply caps replaced.

Pic 4: DENON RCDM41 lots of weird issues with this one. A bodge yes I didn’t have the values and was stumped on this device for a while. Quite a few of the mainboard SMDs had 20 plus ohms so I replaced them. The fault ended up being a tiny passive filter on the power supply being somehow semi open circuit :wtf:

ReeceyBurger123 03-08-2022 01:00 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
1 Attachment(s)
Spot the fake cap too!

momaka 03-26-2022 08:26 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
Quote:

Originally Posted by kc8adu (Post 1113419)
Motorola quantar repeater supplies burn up just like that.
And its leaking electrolyte that set it off.
I recap them on sight.
Just did one for a uhf p25 system i am putting on the air.

Cool, thanks for sharing.
So it was the electrolyte, as I suspected.
Perhaps Nichicon PL series are to be avoided/removed as well - at least at this age now. The PR series sure do like to leak from the bottom.

BTW, glad to see you're back! :) Been a while since you posted on BCN. Hope you were well all this time.

Quote:

Originally Posted by ReeceyBurger123 (Post 1115532)
Some caps for you guys:

Pic 1: Cambridge Audio 15,000uf 63v causing dc error suspect voltage collapses because of these…..

Looks like a "high-end" amplifier... yet full of Xunda (and other?) crap caps.
Sad. :|

Quote:

Originally Posted by ReeceyBurger123 (Post 1115532)
Pic 2: Nichicons out of a Bose thing causing no power, all SMD caps had to be replaced in the device too as you can see.

Running too hot, perhaps?? :confused: Otherwise, why would those Nichicon's die?

Quote:

Originally Posted by ReeceyBurger123 (Post 1115532)
Pic 4: DENON RCDM41 lots of weird issues with this one. A bodge yes I didn’t have the values and was stumped on this device for a while. Quite a few of the mainboard SMDs had 20 plus ohms so I replaced them. The fault ended up being a tiny passive filter on the power supply being somehow semi open circuit :wtf:

Hey if it works, it works. I see Nichicon PW, so it's not a total bodge. ;)

Quote:

Originally Posted by ReeceyBurger123 (Post 1115534)
Spot the fake cap too!

The Nichicon FW maybe? :why: IIRC, those are gold with black writing, no?

PeteS in CA 03-27-2022 06:02 PM

Re: The Hall of Shame - Badcaps Photo Montage
 
The PL and PR series were discontinued long ago, casualties of RoHS. The reconstituted the PL series as the PM series, and due to customer demand brought back the PR series as the PS series. I know they did more changes to the PS series than than just making it RoHS-compliant. So the newer series probably have an electrolyte other than the one(s) that caused problems.


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