Questions about testing caps

[Rapideye]

Hello again all,
got a couple of quick questions here:

What can i use to test some caps in a board, how should this be achieved and what should i look for?

Im soldering on with my first capping project (old abit SH6), just waiting for some replacement caps, the old ones came out ok, holes cleaned up nice and i used a marker pen on the back side to mark the solder points and a few notes (in case i forgot).

Ive got a problem shuttle board that i want to check the caps on, they have visually passed, but i want to test them all to make sure.

Thanks in advance.

[yanz]

Re: Questions about testing caps

esr meter. there are some discussion about esr meter in this forum.
i'm afraid you have to desolder the cap from the board and do a direct measurement.
or further more you may want to use an osciloscope.

crap caps can be visually fine, but rotten inside. tell us the brand (of the caps) we can tell you if they're good quality or not.

i myself have many shuttle boards with green crappy gloria caps, so im sceptical that yours are of good brand caps.

[Rapideye]

Re: Questions about testing caps

Th caps are:
4x Blue OST 16v 1500uF (top 4 caps)
8x Black OST 10v 3300uF (cpu socket)
6x Blue OST 10v 1500uF (atx power, northbridge, agp, ram)
10x Green OST 10v 1000uF (random places around the board)

http://eu.shuttle.com/archive/en/prod/mb/600/fb61.jpg

all seem visually ok, but like you said they could be bad.

Many thanks

[Rapideye]

Re: Questions about testing caps

Hers is a nice detailed pic, there are some changes form the one above, as thios board is a different revision:
[/IMG]

[yanz]

Re: Questions about testing caps

did i hear you said the board is having problem?. what problem exactly that you see? i don't want to be in position to tell that all ost are bad. i'll tell you this, i've seen the purple(blue), black, and green ost bulging/leaking on ecs/asus mobo, some are with crap psu, some are with good psu.

if you want to fully use the boards without having fear when it will get crappy, i would suggest you to recap the board. but if this board run flawlessly and you decide to leave it as it is, that's pretty logical too. only when something bad begin to happen, the idea of recapping should come to your mind.

do some method to check if the problem persist in your other hardware or it is really in your motherboard... have you read our faq section? it will give you some idea about the potentially bad caps from crap brands and how to treat them.

[Rapideye]

Re: Questions about testing caps

Here is the initial problem:
http://www.wimsbios.com/phpBB2/viewtopic.php?t=8484

I now have my multimeter, any pointers on how and whta i should test frist.
Any links to comprehensive sites that would assist me, as i prefere to study up on things first.

[Tom41]

Re: Questions about testing caps

While we're on the subject of ESR meters and multimeters, is it possible to measure ESR without removing the cap from the board? What difference (if any) would it make to the ESR reading if you measured the cap in situ, rather than desoldering it?

With a multimeter, if you measure resistance on a cap, the battery in the multimeter will start to charge the cap. The resistance should keep going up and up, eventually reaching infinity - or at least, higher than the meter can read. If it reaches a point and stays there, the cap could be 'leaky'

[Rainbow]

Re: Questions about testing caps

There are usually more caps connected in parallel so you'll have to desolder them to get some real results. ESR meter works best on caps that are "alone" (like caps in PSUs or monitors).

[Rapideye]

Re: Questions about testing caps

ATTN: ADMINS

Can the admin please close, and route this post to here:
https://www.badcaps.net/forum/showthread.php?t=2466

Ive made the new post complete and informative, thanks.