Panasonic FC series - leaking? quality gone?

[Wester547]

Re: Panasonic FC series - leaking? quality gone?

Sorry, it was just a suggestion, wasn’t trying to dictate the general consensus. Rubycon MCZ and MFZ have issues pertaining to heat failures but they are not known to fail just sitting unused. MBZ are fine as long as you don’t abuse them. Panasonic FC aren’t “bad” in the sense that they are completely crap (“doomed to failure”) a la Sacon FZ but the fact that we have multiple members reporting them repeatedly leaking in cool environments after a decade, and now leaking unused, is worrisome (I don’t think datecode is a factor). This is similar to the quaternary ammonium salt capacitor plague of the late 80s / early 90s. They were known to cause various problems in ECUs and what not. They were not failing just because they were overstressed, as the bungs were deteriorating faster than conventional electrolytics.

But I guess you have a point - Sanyo WG and WX aren’t on the “bad” list but I (and momaka) have seen one or another bulge and leak just sitting in storage with respect to early batches, just like failure prone batches of KZG/KZJ/HM/HN/HZ and crap brands. Would I personally label early batches of WG and WX “troublesome” because of this? Yes, but I suppose you’re right, it’s a matter of opinion and not an objective topic. Samxon for an example is generally considered a good brand here although some have had issues with that one brand (and not just with the GF and GK series either).

[Per Hansson]

Re: Panasonic FC series - leaking? quality gone?

i was wondering if a disclaimer should be added at the end of this post and this post which warns about panasonic fc's problem? It's still on the “good listing” as of now.

Well, you have Nichicon HM & HN on that list without a warning too, I added it now.
And we all know (well some know) that Rubycon MCZ and even MBZ can have troubles with heat.
Point is the "troubles" is still 100x times less than some other problematic brands.
So where do we draw the line? I would certainly like to see more documented failures than this to rule them as bad.
Hell, even UCC KZG and Nichicon HM is only affected for a certain date range, maybe same here?

[momaka]

Re: Panasonic FC series - leaking? quality gone?

note that they lasted over 87000 hours.
thats continuous.
sounded worse than it was.
but leaking and corroding unused parts?
not good!

87000 hours is pretty good.
But the leaking from the bottom part is what worries me a bit, as electrolyte can be corrosive and eat away traces. I'd much rather have a cap bulge and stop working that way instead of leaking from the bung.

Glad I haven't used FC that much, then. I did use FM in previous repairs quite a bit, though. But those having aqueous electrolyte, I don't image they have the same problem.

Also, I have some FC caps pulled from an old Pentium II motherboard, and note of them have leaked. Same in an old Astec PSu.

damn and i wanted to get a shitload of 100uf 16v panny fc for recapping audio decoupling caps with better ones. guess i'll remove the item from my shopping cart. any other recommendation for ultra low leakage current gbl based caps for audio decoupliong?

If you want low leakage, then honestly just go with regular GP 85C caps (or 105C caps if really needed.) 85C caps on a motherboard may not sound like a good idea, but for the audio section, it hardly matters at all, as there is not much heat or stress in that area.

Or if you want to be fancy, Nichicon KT and KA are specifically made/rated for audio use (from what I remember when comparing the datasheet to other caps, these audio caps have lower leakage and higher low-frequency ripple rating.).

That said, you probably won't get much difference in sound when upgrading those caps. So instead, maybe try going with 220 uF caps, as that should give better bass / lower low-cutoff frequency. And if you really want to improve quality - at least when it comes to using non-amplified headphones directly connected to the mobo audio, then build/get a dedicated (headphone) amplifier and remove any series output resistors it may have on the output.

[Wester547]

Re: Panasonic FC series - leaking? quality gone?

Rubycon YXF is another excellent series which has proven itself worthy in terms of long-term reliability, although it's an ethylene glycol based series IIRC but with a very good endurance rating.

I was wondering if a disclaimer should be added at the end of this post and this post which warns about Panasonic FC's problem? It's still on the “good listing” as of now. I'm also curious if the series it replaced, Panasonic FA, another non-aqueous series with identical ripple current and ESR ratings but slightly different and larger cases sizes, discontinued twenty years ago, has this problem as well (I'd hazard a guess that it does). It's probably not as pressing seeing as how it was discontinued so long ago. But it would be a pity if Panasonic was still manufacturing problematic caps to this day.

[stj]

Re: Panasonic FC series - leaking? quality gone?

audio decoupling, i like rubycon YXF's - they seen to give better lows.
one day i may bother to lot an esr frequency curve for a few caps,
i have a scope now that has an ethernet interface.

[Wester547]

Re: Panasonic FC series - leaking? quality gone?

damn and i wanted to get a shitload of 100uf 16v panny fc for recapping audio decoupling caps with better ones. guess i'll remove the item from my shopping cart. any other recommendation for ultra low leakage current gbl based caps for audio decoupliong?

Chemi-con LXZ is another gamma butyrolactone based series that seems to match Panasonic FC’s leakage current spec and case sizes going by the datasheet (and they seem to be available at the regular, authorized distributors), although the datasheets suggest the specs may be slightly different for the 100uF 16V models. LXZ is also certified for automotive usage, and has a higher endurance rating. As far as I know, LXZ have no problems with leaking from the bung after long term usage or storage. And in the event that FC retaining the quaternary salt as their solution is the real reason for this problem, Chemi-con issued a confirmation notice stating (over sixteen years ago) that none of their series (in production at the time) use the quaternary salt electrolyte (LXZ included). Link to an old post I made in which the notice is enclosed.

[kc8adu]

Re: Panasonic FC series - leaking? quality gone?

note that they lasted over 87000 hours.
thats continuous.
sounded worse than it was.
but leaking and corroding unused parts?
not good!

[ChaosLegionnaire]

Re: Panasonic FC series - leaking? quality gone?

damn and i wanted to get a shitload of 100uf 16v panny fc for recapping audio decoupling caps with better ones. guess i'll remove the item from my shopping cart. any other recommendation for ultra low leakage current gbl based caps for audio decoupliong?

[kc8adu]

Re: Panasonic FC series - leaking? quality gone?

had a power supply for an apple 2e i repaired 10 years ago come back to me .
all the fc were leaking from the bung.
unit runs 24/7/365 and cool.
this is not good!

[stj]

Re: Panasonic FC series - leaking? quality gone?

one thing i'v noticed with leaking caps regardless of make - it's usually the same leg.
i think the negative.

could it be some type of electrolysis drawing the fluid to that side?

[redwire]

Re: Panasonic FC series - leaking? quality gone?

1st response from Panasonic rep:
"... I would not use a part that had corrosion on the leads. It could effect the performance. Sounds like moisture got into the packaging. Please let me know if you have any questions."

I won't store them in the rain lol
I guess FC's have some seal problem if they are leaking even before being used. Sad.

[stj]

Re: Panasonic FC series - leaking? quality gone?

all the bad ones had been in use atleast 10years

[Wester547]

Re: Panasonic FC series - leaking? quality gone?

Yup.
FC is also one of the few series rated for automotive applications. And we all know how "not-so-easy" the environment inside a car can be on components. So I'm really hoping this is just an isolated case or maybe just a bad batch/run of the week at most.

stj said he's seen lots of FCs leak and kc8adu had this happen a while back. This might be normal after a decade or so - just like the quaternary salt capacitors from three to four decades ago.

Correct.
What's interesting is that on these caps, the ESR and capacitance were still in spec the last time I checked them a year ago (or was it two now? ) Only reason I've been reluctant to use them is because I don't want them to leak and destroy PCB traces, which electrolyte will easily do. So far, those 16V, 100 uF PM caps have been the only ones I've had issues with. All others (including other sizes/capacitance Nichicon PM) have been OK.

I remember you observing the case size of the 100uF 16V PMs were 5x11 - bewildering, seeing as how the datasheet says they're supposed to be 6.3x11. I noted this back then too, but unless they're actually 6mm, I wonder why they wouldn't match the datasheet's specs? Did Nichicon improve the manufacturing process, allowing them to reduce the case size? Hope they're not counterfeits.

Is that the Panasonic (if not still Matsushita) version of KZG?! Yikes!

Unlikely. Stj said they're (the FCs) never domed, only that they leak from the bung. The failure mode is different and I'd guess not as fast. Probably no outgassing either.

[RJARRRPCGP]

Re: Panasonic FC series - leaking? quality gone?

i have seen lots of leaked FC's and mentioned it atleast a few times.
always around the bung, and they are never domed.

i have not seen the same issue on FM or FK.

Is that the Panasonic (if not still Matsushita) version of KZG?! Yikes!

[momaka]

Re: Panasonic FC series - leaking? quality gone?

The bung hasn't even been through reflow or any soldering.
It's a high-end part with AEC-Q200, 5,000hrs 105°C

Yup.
FC is also one of the few series rated for automotive applications. And we all know how "not-so-easy" the environment inside a car can be on components. So I'm really hoping this is just an isolated case or maybe just a bad batch/run of the week at most.

Momaka’s Nichicon PMs, going by the original revelation he posted, leaked around four years ago now (after only five years in storage judging by their datecodes).

Correct.
What's interesting is that on these caps, the ESR and capacitance were still in spec the last time I checked them a year ago (or was it two now? ) Only reason I've been reluctant to use them is because I don't want them to leak and destroy PCB traces, which electrolyte will easily do. So far, those 16V, 100 uF PM caps have been the only ones I've had issues with. All others (including other sizes/capacitance Nichicon PM) have been OK.

[Wester547]

Re: Panasonic FC series - leaking? quality gone?

Looks like it was made in either February of 2006 or 2016. I'd hope the former because only new cheapos should leak after 3~4 years of sitting in storage (13~14 years would be more reasonable although still disappointing)...

[redwire]

Re: Panasonic FC series - leaking? quality gone?

6201MC, DF is 0.25, ESR is good.

[Wester547]

Re: Panasonic FC series - leaking? quality gone?

What does the datecode on the FC say? I know how to decode Panasonic’s date decoding format and as do other members here. I guess it can’t be that old - probably less than a decade old. Momaka’s Nichicon PMs, going by the original revelation he posted, leaked around four years ago now (after only five years in storage judging by their datecodes). That Panasonic FC would be exhibiting this type of behavior, along with Nichicon PM, is equally confounding. I only know of two types of capacitor “plagues” which caused Japanese electrolytics to leak from the bung with no notable hydrogen gas production - the quaternary ammonium salt plague from the late 80s / early 90s (which should no longer be an issue) and a separate problem from that time frame and a bit later with 85ºC capacitors and SMD capacitors having problems with rubber bung deterioration (and leakage thereafter).

It would be a pity if Panasonic FC ended up having this problem. I know a number of members have used them here in their repairs before, and it would suck if this comes back to bite them.

[redwire]

Re: Panasonic FC series - leaking? quality gone?

The bung hasn't even been through reflow or any soldering.
It's a high-end part with AEC-Q200, 5,000hrs 105°C and last time I saw this was on 30 year old Spragues. I emailed Panasonic to see if they will comment.

Panasonic FC series has been my go-to for replacements in vintage gear. Not SMPS where low ESR is essential, but instead for audio gear. I'll have to find something alternate I guess.

[stj]

Re: Panasonic FC series - leaking? quality gone?

the bung hardens over time - maybe because of an interaction with the electrolyte,
maybe because of the humidity or temperature of the enviroment.

i have seen lots of leaked FC's and mentioned it atleast a few times.
always around the bung, and they are never domed.

i have not seen the same issue on FM or FK.