Identifying Proper Replacement Caps...?

[cprince]

Hello all!

Awesome site! You guys are all awesome with your self sufficiency and obvious bravery in sticking a 450C chunk of metal in your sensitive and often expensive electronic bits!!!

Love it!

I am working on an IBM ThinkVision 19 inch LCD monitor. I got it for free from work.

The symptoms;
Plug it in to the wall and the unit's "splash screen" (It says IBM ThinkVision when the monitor powers up) strobes slowly; one image pulse for about a half second every 5 or 7 seconds.

Makes no difference if there is a VGA or DVI signal input or not.

My cracker-jack diagnosis is that it must be power related to be cycling like that. I opened it up and had my suspicions confirmed. There are 5 caps that are about 1.5 CMs and one that is about 1.0 CM. Four out of the five 1.5s are popped and the 1.0 is as well.

My thinking is to replace them all as they are made by CapXon. After a quick search in here I have discovered that they are FAR from being of a high quality.

My problem is that I have no idea what I am looking for in the way of a replacement. The values that are on the side of these buggers are hard to make out and the information that I have been able to get off of them do not seem to be sufficient to make a reliable match.

When I go to one of the suggested suppliers (I live in Canada) http://search.digikey.com/scripts/Dk...dll?Cat=131081 the selection makes my eyes water.

This is what I can read on the originals;

There are five that are the same size, and mounted vertically, (1.5 CMs) Of those 5, 3 are identified with these numerical values;
C352
GL105c (105 degrees Celsius I am certain)
Vent (The scored top I suppose)
10v (voltage I gather)
1000uF (Capacitance)

The other 2, 1.5CMs;
C350
GL105c
Vent
25v
470uF

The 1.0 is mounted horizontally and has these markings;
C350
Cant see the temp rating
Vent
25v
220uF


The info that seems to be missing for me to make an informed choice is;

ESR
Feature (Polarity - Steel Case - GP or PC Grade....)
Lead Spacing
Life time (That one is kind of easy...)
Mounting Type (Not certain... through hole?)
Package Case (Radial - Axial... many choices here...)
Series
Size dimension (I can use a measuring tape but... not to the mm... my eyes aren't THAT good...)
Surface Mount Land Size - Are you kidding?!
Tolerance

So... evidently... I have FAR too many choices.

Any and all help and/or suggestion would be welcomed and greatly appreciated.

Thanks all!

Craig

[PCBONEZ]

Re: Identifying Proper Replacement Caps...?

Those are GL series. (Letters before the temp.)
You want the same or more ripple and the same or less ESR.
(If they are general purpose ESR might not be listed.)
Here a link to Capxon data sheets.
http://www.capxongroup.com/en/prod_all_cat_full.aspx

[PCBONEZ]

Re: Identifying Proper Replacement Caps...?

BTW: ESR is Impedance in that table.

[cprince]

Re: Identifying Proper Replacement Caps...?

You know... I am not feeling any brighter.

I see some possibilities of what I am looking for through the process of elimination... but I am really not certain.

I have no idea what the impedance is on these caps... I do not know what ripple is nor how to find out what ripple I need.

I appreciate showing me the link to the data sheet, and I am not looking to be spoon fed... but I am lost. I didn't know that there was so many variants between caps.

Craig

[PCBONEZ]

Re: Identifying Proper Replacement Caps...?

Go to link I gave.
Click on GL, it brings up the data table for your old caps.
Pick one of your caps by the uF and volts printed on the side and look up ESR and Ripple.
Then look up that uF and volts at digikey, open the data tables of those the search brings up and compare ESR and ripple ratings to what you have.

Starting here:
http://search.digikey.com/scripts/Dk...ords=capacitor

I check the boxes for "in stock" -> apply filters
Then package type = "radial" -> apply filters
Then all the max temp's that are 105c -> apply filters
... before I enter the uF and volts and -> apply filters again.
-
Don't usually need to specify other things because they tend to fall into place anyway with those filters used.
-
That data sheets are linked to in the right hand column. - [I forgot which brand now but last time I searched there the links to one brand weren't working because that brand changed their site and digikey hasn't updated the links yet.]

I dunno what size caps you have there but looking at a GL series 1000uF 6.3v 10mm as a sample I get: Ripple/ESR of 620/0.120
That's just barely a low ESR cap.
Probably 80% of what digikey's search brings up will be rated better.
Off the top of my head KMG and VZ probably aren't rated that good but most ot the others should be.


.

[cprince]

Re: Identifying Proper Replacement Caps...?

Good man PCBONEZ!

I have been messing around going between the data sheet and digikey's website trying to figure this all out..

The only things (I think) that I am not certain about is the "Series". Does this matter? I would think that the "GL" series is a proprietary thing. That being said, then series doesn't matter much... right?

The other is the impedance translation; On the spec sheet at CapXon, my Cap 220uF rated 25volt 8x11.5 gives me 0.125 impedance. How does that translate/convert into mOhm? 12.5? 125.0?

One more thing that I am just assuming is that my caps are Electrolytic - Aluminum. It *seems* to fit the bill.

I think I am "getting" it all! I appreciate your patience with a total know nothing!

[PCBONEZ]

Re: Identifying Proper Replacement Caps...?

Series is like a base model number or type or grade or class from that brand.
This series will have higher ESR and Lower temp ratings than that Series kind of thing.
The Series name is only for caps of whatever brand but after a while you know that xy series from this brand is equivalent to (or better or worse than) ab series from that brand.

GL is just the Series of the old Capxon caps.
Some other brand may happen by chance to use "GL" as a series name but those probably won't be the same as Capxon's GL.

The units is a note at the bottom on that one.
0.125 is ohms at 20c and 100 kHz. [And so 125 mOhms]
-> 20c and 100 kHz is the accepted standard condition used in ESR ratings.

Don't worry too much about Lifetime. The number is nearly meaningless.
It is the number of hours the cap can be operated at max temp, max ripple, max volts, all at the same time, and NOT damage the cap at all. If in the real world a cap is ever at those conditions then someone picked the wrong cap to start with.
.

[cprince]

Re: Identifying Proper Replacement Caps...?

Origionals:
CapXon Gl series


Original:
3x 10x16
C352
GL105c
10v
1000uF
1010 Ripple
0.072 Impedance


Replacement:
United Chem - KZE series
http://search.digikey.com/scripts/Dk...me=565-1646-ND

1430 Ripple
0.038 Impedance

10@ $4.03

-----------------

Original:
2x 10x16
C350
GL105c
Vent
25v
470uF
1040 Ripple
0.065 Impedance

Replcement -
United Chem - KZE series
http://search.digikey.com/scripts/Dk...me=565-1677-ND

1430 Ripple
0.038 Impedance

10@ $3.98
----------------------

Original:
1x 8x11.5
C350
25v
220uF
550 Ripple
0.125 Impedance

Rplacement -
United Chemi-Con KZE Series
http://search.digikey.com/scripts/Dk...me=565-1674-ND

760 Ripple
0.072 Impedance

10 @ $2.53

-----------------

All replacements are as you suggested; Greater ripple value and lower impedance. I thought that I would go ahead and buy 10 or each for any future needs and possible screw ups on my part!

On a related note; how does one test capacitors? I have a volt/ohm meter... not certain that it would cut it...

Craig

[kc8adu]

Re: Identifying Proper Replacement Caps...?

for monitors panasonic fc is a good choice too.often better availibility.

[PCBONEZ]

Re: Identifying Proper Replacement Caps...?

KZE are fine. FC and PW are also good.
Check the per 10 pc prices for the FC and PW too.
It's odd but often at digikey the per each doesn't follow the per 10 on which are more or less $$$. In 10pc Qty the others may be less than KZE.

[cprince]

Re: Identifying Proper Replacement Caps...?

for monitors panasonic fc is a good choice too.often better availibility.

I looked at those... but I noticed that the ripple and the impedance was no where near the KZE. That was what I thought I should base my replacement choice on...

[PCBONEZ]

Re: Identifying Proper Replacement Caps...?

As long as you match or beat the originals you are fine.
Capxon don't go bad for being under rated as new. (As in the data sheet.)
Aluminum sourced in TW and CH has impurities that break down the electrolyte at a younger age than caps made with Japanese, UK, or US sourced Aluminum. Once it breaks down the caps don't live up to the data sheet values anymore.

[cprince]

Re: Identifying Proper Replacement Caps...?

Replaced the who enchilada... and it works perfectly! Got lucky... I had nothing to practice on, so my first cap was done live!

My soldering iron is old and bent to crap and I used plumber's flux paste... but it works. And it even looks like I knew what I was doing.

One question; There was one cap that was horizontal... I put it in vertical... big deal? There are no clearance issues or anything else that would show this as being a problem...