Marking on electrolytic capacitors

[debjit625]

Hi this is my first post...

I was looking over a motherboard and I found some electrolytic capacitors, radial lead types having marking of "221 16V" I guess it is 220 micro farad 16 volt,but I never seen this kind of marking on an electrolytic radial lead capacitor PTH types,its very common on SMD electrolytic capacitors.

Their are some more capacitors and their marking are like these "K581 6.3V" it may be 580 mfd and "K681 6.3" it may be 680 mfd.

I can check them but I am asking you guys first...

Am I correct?

[PCBONEZ]

Re: Marking on electrolytic capacitors

Best guess.
220uF 16v
680uF 6.3v
.
There is no standard [industry requirement] for the marking method.
They can use any method they want on any kind of cap.
At first direct printing was least expensive way.
Then using sleeves became less expensive.
Now direct printing is cheaper again. [More advanced printers.]
~ But most factories are already set up to support using sleeves.
.

[debjit625]

Re: Marking on electrolytic capacitors

Thanks...

[PCBONEZ]

Re: Marking on electrolytic capacitors

If you show some photos someone might recognize the brand.
[If you care.]

[Agent24]

Re: Marking on electrolytic capacitors

I'd be interested in seeing a photo, never heard of electrolytics using 3-digit codes before either

[PCBONEZ]

Re: Marking on electrolytic capacitors

never heard of electrolytics using 3-digit codes before either

Common on ink marked caps.
Also very common in the part number in the data sheet.
.
Like so
R33 = .33 uF
3R3 = 3.3 uF
330 = 33 uF
331 = 330 uF
332 = 3300 uF
.
See Part Number column.
.

[debjit625]

Re: Marking on electrolytic capacitors

It's a running motherboard with no problem ,so I don't want to desolder the capacitors.
Some how I managed to take a few photo while they were on the board...


Its a Zebronics motherboard old 845 chipset (GMCH) with P4
http://www.zebronics.com/

As I am learning to repair motherboards ,I just gave a look on it for better understanding of older motherboards.And I found it weird...

[Agent24]

Re: Marking on electrolytic capacitors

It's a running motherboard with no problem ,so I don't want to desolder the capacitors.

Well if they look like the ones in your photos then it does have a problem, and it won't be running for much longer

Common on ink marked caps.
Also very common in the part number in the data sheet.
.
Like so
R33 = .33 uF
3R3 = 3.3 uF
330 = 33 uF
331 = 330 uF
332 = 3300 uF
.
See Part Number column.
.

But yeah, I've never seen aluminium can electrolytics without sleeves marked with a code rather than straight values like that before - you certainly do learn something every day!

[mariushm]

Re: Marking on electrolytic capacitors

I think both have issues.

The second is obvious, swollen... replace it. I think that one's 580uF 6.3v.
The one in the first picture looks to me like it's bottom is coming out, maybe inside gasses pushing it outside.. if so it's going bad so you should replace it.

If you want, post one or several pictures of the board, maybe our eyes can spot other possible issues or faulty capacitors.

Also keep in mind that if that capacitor is swollen chances are the ones in the same area were also abused in the past and on their way out, so you may have to replace others even if they look good.

[debjit625]

Re: Marking on electrolytic capacitors

Yes I know their is a problem with the second one but the first one seems all right, but again ESR can't be guessed by just looking at the capacitors so I will check them...

The one in the first picture looks to me like it's bottom is coming out

No it has been soldered like that, I have already checked it. I think the manufacturer did that mistake, but the board is good enough as it’s giving a service of 4 + years .

I just found the marking weird, so I thought may be only I don't have seen something like this before, but now after all your replies I am sure its weird...

Anyway when I will replace them, I will check the values of the capacitors and confirm it on this thread.

Thank you all

[Agent24]

Re: Marking on electrolytic capacitors

I just found the marking weird, so I thought may be only I don't have seen something like this before, but now after all your replies I am sure its weird...

Not really weird, just uncommon I suppose. The markings isn't what's wrong with them, it's the bulging!

I can't see any brand or logo in your photos, do they have anything by the way?

[debjit625]

Re: Marking on electrolytic capacitors

can't see any brand or logo in your photos, do they have anything by the way?

No,they just have the value ,voltage and polarity marking...

And I didn't mean weird in that sence...yes more like uncommon.Even I think they are not commercial they are only available to the manufacturer.

[PCBONEZ]

Re: Marking on electrolytic capacitors

It's a running motherboard with no problem ,so I don't want to desolder the capacitors.
Some how I managed to take a few photo while they were on the board...


Its a Zebronics motherboard old 845 chipset (GMCH) with P4
http://www.zebronics.com/

As I am learning to repair motherboards ,I just gave a look on it for better understanding of older motherboards.And I found it weird...

That's a 'no name' brand with a silver colored sleeve.

[hectoroki]

Re: Marking on electrolytic capacitors

Maybe you can just check sizes.. and on a electronic dealer page.. just try to match something similar to the size and supposedly capacity?? .. well just my opinion..

[PCBONEZ]

Re: Marking on electrolytic capacitors

If you can show some pics of the board and where the caps are we can guess what ESR grade they need to be.
[Probably nothing fantastic anyway given their size.]
.
580uF is a weird size. You won't find it in a 'good brand'.
I'd up it to the next standard size. [680uF]
.
Lacking more info....
In general FC, PW, KY, LXZ or similar is fine for the 220uF 16v.
The other one 'might' actually need to have decent ESR so I'd use an FM or FR just to be on the safe side.
.
Could probably recommend places to buy good caps but I dunno where in your solar system.
.

[debjit625]

Re: Marking on electrolytic capacitors

580uF is a weird size. You won't find it in a 'good brand'.

Yes you are right but again the board is giving a very good service so may be thats the best stuff for it...at the VRM section they used 3300 mfd and 680 mfd...

Could probably recommend places to buy good caps but I dunno where in your solar system.

Thanks anyway ,I know a lots of places to buy good caps.And I am from India,Kolkata

Maybe you can just check sizes.. and on a electronic dealer page.. just try to match something similar to the size and supposedly capacity??

Many capacitors have identical value and packaging but differs a lot for example low ESR,of course I thought they should have some kind of different marking on them but after looking at the example caps above I am not sure anymore...

[kamalkhandal]

Re: Marking on electrolytic capacitors

Hey Debojit,Did 680 worked for u and did u got 580 or replaced it with 680 too.please post as I am having same problem.

[Rulycat]

Re: Marking on electrolytic capacitors

GSC/Evercon made silver caps like those.