Samsung SyncMaster 215TW crappy caps

[tmx1]

I just thought I would share my experience with the SyncMaster 215TW LCD.

Last week i heard a buzzing noise coming from the back, then early mornings when i turned on the LCD, it would power on for 1-2 seconds and power off by itself... i had to repeat this process 5-10 times before it would keep itself powered ON.

I figured it may be a cap issue and did some research.. and surely enough i was right.
Here is a picture of the power supply board for this monitor..

http://img256.*************/img256/6537/img2095t.jpg

[EGuevarae]

Re: Samsung SyncMaster 215TW crappy caps

I just thought I would share my experience with the SyncMaster 215TW LCD.

Last week i heard a buzzing noise coming from the back, then early mornings when i turned on the LCD, it would power on for 1-2 seconds and power off by itself... i had to repeat this process 5-10 times before it would keep itself powered ON.

I figured it may be a cap issue and did some research.. and surely enough i was right.
Here is a picture of the power supply board for this monitor..

http://img256.*************/img256/6537/img2095t.jpg

Welcome.
Replace all the brown caps, even the non bulged ones. Post info on them (capacitance, voltage rating and brand/series) and replacements would be suggested in no time.

[tmx1]

Re: Samsung SyncMaster 215TW crappy caps

Welcome.
Replace all the brown caps, even the non bulged ones. Post info on them (capacitance, voltage rating and brand/series) and replacements would be suggested in no time.

CapXcon 820uF 25v and 330uF 25V.

I just packed it and send it off for RMA since i still had a few months warranty.. heh i already pulled out the caps though..

But i got another one of these 215TW LCDs here and its making the same buzz noise, so its only a matter of time before it dies.

[Freezer]

Re: Samsung SyncMaster 215TW crappy caps

I recently got a broken Samsung 215TW off craigslist. This monitor is 21" widescreen with CCFL backlights. Before I get to the repair, I wanted to note some observations on this monitor. Most monitors have maybe two video inputs, this monitor has 5 (DVI, VGA, component, composite, and s-video). It also has built in speakers (which I'm sure sound flat), and a very elaborate stand. The stand goes up and down, screen tilt, plus the screen can be rotated to portrait, and as if that's not enough, the entire base swivels almost 360 degree around. I've heard that this monitor cost over $500 new, and seeing all it's got I can believe it.

Anyway, back to the repair. The person who gave me this monitor said the image would flicker. I never even turned it on, the first thing I did was open it up. As I suspected the problem was bad caps. I found 5 bulging caps inside. I ended up replacing a total of six caps. After the recap the monitor runs beautifully.

Here are the details about the caps I ended up replacing. All the bad caps were CapXon brand. The big fat cap on the board was Samxon brand and I did not replace it.

Location / Rating / Measured Capacitance / Measured ESR
C107 / 47uF50V / 48uF / .6ohms
C110 / 820uF25V / 258uF / 1.4ohms
C111 / 820uF25V / 182uF / 2.0ohms
C112 / 330uF25V / 21uF / 10ohms
C301 / 330uF25V / 25uF / 14ohms
C302 / 330uF25V / 26uF / 11ohms

From these numbers the cap at C107 was probably alright, but I replaced it nonetheless. All the other caps were very low on capacitance and high on ESR, not to mention the bulge on top.

Total this cost me $2.40 in replacement parts from digikey.

Again thanks to everyone on this board, everything I've learned from others helped me in this repair. And hopefully my post will help someone else.

[potentially_ignorant]

Re: Samsung SyncMaster 215TW crappy caps

First of all, thanks to Freezer for posting those pictures with notes on the capacitors. Until I saw that post, I thought C301 and C302 were rated at 30 microfarads, not 330 microfarads. Also, I referred to those component notes in this post.

My parents have a Samsung Syncmaster 215TW with the same issue Freezer described, and is also described in this thread begun by Jinatra; the monitor flickers (and has been getting worse over time) when it first starts displaying a signal but if you give it time to "warm up" it displays a stable image. This also occurs if the monitor has been on, but is allowed to enter sleep mode for about 30 minutes, currently. I was originally going to try the board replacement which is described in this blog post by wcoastsands. Unfortunately, the replacement power supply board for this monitor is proving difficult to find.

So, I opened up my parents' monitor and C110 and C111 are both visibly bulging at the top. I have attached pictures because I cannot tell if any of the others are bulging "fatter" than they should be; I'm not really that familiar with electronic components. I have put together my own PC, replaced components in the PCs of others and made Ethernet cables, but I have never soldered and I don't even own a multimeter (though I have heard of them before). That said, I have some questions before I start ordering parts.

First question: Are any of the other capacitors visibly damaged? I can't tell if any of them appear to be fatter than they should be. I understand I should probably take this opportunity to replace all of the CapXon capacitors (I don't plan on replacing the very large green SamXon capacitor), but if for some reason I cannot replace all of them, then I plan to replace the damaged ones only (currently C110 and C111). I am also concerned about the way C107 is bent. Is it harmless for a capacitor to be leaning like that?

Second question: I haven't found anyone saying which capacitors they have used to replace the capacitors on this board, so far. How close do the various specs of the replacements need to be to those of the original capacitors? In one of the comments on the blog post linked above, someone mentioned they replaced they replaced the two capacitors rated at 820 microfarads with capacitors rated at 1000 microfarads. What I've read so far about capacitors seems to point towards that being a bad idea and that you should use the same capacitance rating. As I understand it, a higher voltage rating is fine because that just means it will be able to tolerate higher voltages. But what about the ESR/impedence rating and the ripple current rating? I found these capacitors by Nichicon on Digikey but those two ratings are slightly different. For comparison, I believe the following is the specifications sheet for the correct series of capacitors used on the 215TW board:

And here is the link to sheet for the PW series by Nichicon, which I've noticed was listed on the BadCaps good capacitors list in the FAQ: https://cdn.badcaps-static.com/pdfs/...382925d157.pdf

Third question: The same blog post comment which mentioned using a higher capacitance for two capacitors also mentioned replacing C107 with something rated for higher temperatures because it is right next to a heat sink. But C110, C111 and C112 are also pretty much right next to a heat sink, and as I understand it these capacitors are rated for 105° C. Granted, C110 and C111 are the two which are obviously bulging at the top in my case, but the monitor has lasted for 5 or 6 years. Would anyone recommend trying to find capacitors which are rated for higher temperatures? If so, what rating would you suggest?

Fourth question: On the subject of temperature, I read somewhere on BadCaps that people were recommending the use of soldering stations which can reach a temperature of 450° C and have a grounded tip. I can understand why you wouldn't want an electrostatic discharge into the board you're trying to repair, but 450° C seems like a lot of heat. Maybe this question is better asked in another part of these forums, but I was wondering why so much heat is necessary to solder. Also, I noticed RadioShack carries a rebranded soldering station by Madell. Anything about that one to be wary of?

[PlainBill]

Re: Samsung SyncMaster 215TW crappy caps

First point, thanks for the pictures, but it's more effective to post just two or three pictures. The first should be a shot from directly overhead showing the suspected card (in this case, power supply / inverter) at as close to 2000 x 2000 resolution as possible. That is usually sufficient to show any bulging caps.

The second picture should be a bottom view of the suspect board at the same resolution. The third is an over-all view of the back side of the monitor (with the back off, of course). If additional pictures are necessary, we will ask for them. Still, I prefer to be overwhelmed with an abundance of pictures rather than seeing one dimly lit out of focus picture taken with a cell phone camera.

Now let's deal with this monitor.

1. My recommendation is to replace all the electrolytic caps except the large 100uF, 450 volt one. It rarely fails. Capxon is a known bad brand.

If you are in the US and order from Digikey a full set of caps will cost less than $10 delivered if you specify USPS First Class Mail shipping.

2. It's a good idea to get as close to the original specs as practical. We aren't dealing with the Space Shuttle here, exact matches aren't necessary. I usually use Panasonic FM series, knowing that they are probably much better than original. It IS important to use low ESR caps that are designed for use in an SMPS power supply.

3. I wouldn't bother trying to find higher temp caps. As you pointed ut, it lasted 5 or 6 years with crap caps, it's going to last at least 5 years more with good quality caps.

4. Unless you are planning on doing many of these monitors, just stick with a soldering iron.

PlainBill

[retiredcaps]

Re: Samsung SyncMaster 215TW crappy caps

but I have never soldered and I don't even own a multimeter (though I have heard of them before).

The best video on soldering is by CuriousInventor at

http://www.youtube.com/watch?v=I_NU2ruzyc4

Badcaps.net also has an excellent written (with photos) tutorial on soldering at

https://www.badcaps.net/forum/showthread.php?t=485

For this particular fix, you can probably get away without needing a multimeter.

First question: Are any of the other capacitors visibly damaged?

Capacitors die from age, heat, and shoddy build quality. Capacitors DO NOT have to be visibly bloated in order to bad. They can be out of tolerance uF (a 1000uF measures 20uF) and/or have high ESR (ohm). A multimeter will be insufficient to test for ESR. For that you need an ESR tester which costs between $50 and $300.

Most members here will recommend that you replace ALL capacitors with reputable brands from reputable sellers. Brands like Rubycon, Panasonic, and United Chemicon are suggested.

I am also concerned about the way C107 is bent. Is it harmless for a capacitor to be leaning like that?

They can lean with no problems.

Would anyone recommend trying to find capacitors which are rated for higher temperatures? If so, what rating would you suggest?

In some instances, Panasonic FR, which is equivalent to FM, has a longer endurance life than Panasonic FM.

[DarkPrognosis]

Re: Samsung SyncMaster 215TW crappy caps

My 215tw decided to suddenly start flickering last week (as if I were watching it at 20-30hz) until it warms up (seems to be taking longer each day to warm up). I will attempt to open this up in a few days and see but if I have no issues once it has 'warmed up' would that be just a bad caps deal or a CCFL deal?

[Th3_uN1Qu3]

Re: Samsung SyncMaster 215TW crappy caps

Bad caps more likely than bad CCFL.

[DarkPrognosis]

Re: Samsung SyncMaster 215TW crappy caps

Well, I use Mouser Electronics but I am not opposed to Digi-Key if anyone would be so kind as to post the part numbers I will just buy them and replace them. I just don't know which ones to get with the ESR I need. I know the voltage and I know the microfarad but ESR is something I don't know much about (brand new term for me) and I don't see that listed on the parts.

[PlainBill]

Re: Samsung SyncMaster 215TW crappy caps

Well, I use Mouser Electronics but I am not opposed to Digi-Key if anyone would be so kind as to post the part numbers I will just buy them and replace them. I just don't know which ones to get with the ESR I need. I know the voltage and I know the microfarad but ESR is something I don't know much about (brand new term for me) and I don't see that listed on the parts.

Nobody is likely to give you a list of part numbers; quite often a given model monitor will have been built with several different power supplies in it's production life. Here is a procedure for selecting caps. This is written for Digikey; a similar process works for Mouser.

PlainBill

[DarkPrognosis]

Re: Samsung SyncMaster 215TW crappy caps

Well, I do know about this part for ordering caps PlainBill, but what I don't understand is matching ESR with ESR since I see nothing anywhere about ESR (I don't even know what that is as I have never ran into it before on caps).

edit: I have been at this all morning and came up with these part numbers for Digi-Key (no cap I could single purchase had an ESR listed via DK) - P10321-ND, P11221-ND, P12387-ND

Will those be fine since they didn't really list an ESR?

[PlainBill]

Re: Samsung SyncMaster 215TW crappy caps

Well, I do know about this part for ordering caps PlainBill, but what I don't understand is matching ESR with ESR since I see nothing anywhere about ESR (I don't even know what that is as I have never ran into it before on caps).

At the frequencies we are dealing with, ESR is equivalent to impedance. There are a few people who insist the ESR of replacement capacitors must match that of the original. I feel otherwise. I've been over this countless times, here is it in capsule form.

There are a number of specs for capacitors. The obvious ones are capacitance and voltage. If you look at the datasheet, you will notice that capacitance is specified to be within a range. For the electrolytic caps we are using +-20%. On the other hand, voltage is specified as a 'better than' value - after a suitable aging period, the capacitor will withstand that voltage forever. It does not say the capacitor will not withstand a higher voltage. Temperature is another 'better than' value. ESR is a third 'better than' value. For my favorite Panasonic FM series, a 1000uF, 25Volt capacitor is rated to last 5000 hours at 105°C, with an applied voltage of 25V and a ripple current of 2.6 Amps.

The ESR (impedance) is rated at .018 ohm. This does not mean the ESR will be .018 ohms on a new cap, it is guaranteed to be below .018 ohms, and to remain below .018 ohms for 5000 hours at full ripple current. There is no assurance that it will not be .010 ohms or even .005 ohms initially.

Several years ago I was faced with a Samsung TV that had half a dozen caps that had 'popped'. The rest of them were visually fine. I used my ESR meter to check all the caps. I wasn't surprised to find the ESR of the bad caps to run well over .5 ohms. I was surprised to find the ESR of the remaining caps to be well below the spec of .05 ohms - typically .01 to .02 ohms. Then I checked the new caps I had on hand. They were rated at .04 ohms, but read .02 ohms. Were they bad? No, they met the spec of 'less than .04 ohms'.

As a result, when selecting caps, I choose Panasonic FM, knowing that they will exceed the spec of the original caps, and avoid wasting my time trying to identify something inferior that matches the original garbage caps the manufacturer installed.

PlainBill

[DarkPrognosis]

Re: Samsung SyncMaster 215TW crappy caps

Very true PlainBill though the issue at hand is that FM is not available in several of those capacitances and voltage rating combos. I always stuck with FM/FC when I used to be a radio amateur and built/repaired a lot of stuff but I never once thought about, or even heard about, ESR.

My thing is that Digi-Key doesn't offer the FM variety, and I am finding it hard to find Japanese parts due to the issue over there post Tsunami, for the items I need.

[PlainBill]

Re: Samsung SyncMaster 215TW crappy caps

Very true PlainBill though the issue at hand is that FM is not available in several of those capacitances and voltage rating combos. I always stuck with FM/FC when I used to be a radio amateur and built/repaired a lot of stuff but I never once thought about, or even heard about, ESR.

My thing is that Digi-Key doesn't offer the FM variety, and I am finding it hard to find Japanese parts due to the issue over there post Tsunami, for the items I need.

Excuse me, Digikey DOES offer FM series caps. It may be that a particular value is out of stock, in which case I have given you enough information to select other series of Panasonic (FC, FR), or from other manufacturers.

PlainBill

[DarkPrognosis]

Re: Samsung SyncMaster 215TW crappy caps

That is what I was talking about so no "excuse you" was necessary. Out of stock also means not available.

Thanks for the help.

edit: Just for future info when using all of your search criteria and not using the check box for in stock and the result I get back is "No records match your search criteria" I sort of take that to mean it is not available period.

[PlainBill]

Re: Samsung SyncMaster 215TW crappy caps

That is what I was talking about so no "excuse you" was necessary. Out of stock also means not available.

Thanks for the help.

edit: Just for future info when using all of your search criteria and not using the check box for in stock and the result I get back is "No records match your search criteria" I sort of take that to mean it is not available period.

Yeah, one of the weaknesses of the search process. On the other hand, if you expand the limits to other brands of caps it eliminates dozens of items that are not in stock.

PlainBill

[PCBONEZ]

Re: Samsung SyncMaster 215TW crappy caps

I checked the new caps I had on hand. They were rated at .04 ohms, but read .02 ohms. Were they bad? No, they met the spec of 'less than .04 ohms'.

.
The accuracy of the common Bob Parker based ESR meter is +/- 1 digit [plus] +/-5%.
So your .02 ohm reading could have easily been actual value .03 ohms +5%.
And that's only if the meter it was accurately calibrated and the battery up to par.
.
While it's reasonable to expect the ESR to be de-rated to some degree to ensure it doesn't go out of spec in use,
It is NOT reasonable to assume it's de-rated markedly.
It is NOT reasonable to assume the degree of de-rating of a good brand is different than the degree of derating of a bad brand. [They do that the same way for the same reasons.]
- Or that a cap rated for .018 ohms or more would also be so low as .005 ohms initially. [If it was actually that much lower they'd rate it lower for more $$$.]
- Or that a cap rated for .050 ohms or more would also be so low as .02 or .03 ohms initially. [If it was actually that much lower they'd rate it lower for more $$$.]
.
.

Several years ago I was faced with a Samsung TV that had half a dozen caps that had 'popped'. The rest of them were visually fine. I used my ESR meter to check all the caps. I wasn't surprised to find the ESR of the bad caps to run well over .5 ohms. I was surprised to find the ESR of the remaining caps to be well below the spec of .05 ohms - typically .01 to .02 ohms.

As ESR goes up with age this sounds like a case of old caps with excessive leakage. - AKA: Partially shorted due to degraded oxide layer [dielectric].
You should have caught that.
.
.

At the frequencies we are dealing with, ESR is equivalent to impedance. There are a few people who insist the ESR of replacement capacitors must match that of the original. I feel otherwise. I've been over this countless times, here is it in capsule form.

.
No, that's not what is said.
The recommendation has always been:
IF YOU AREN'T GOING TO DO THE MATH, then stick as close to the original values as possible.

In regards to blanket across the board [universal] advice that's only -responsible- advice that can be given.
-- HERE IS ONE EXAMPLE OF WHY:

Following PI circuit and component values taken from a Viewsonic Power/Inverter board.
- PI filter redrawn to show parallel Ripple Current paths.
.

-
12v circuit.
-
Coil 0.6uH [@ 100kHz => 0.3770 ohm -- This high value for ohms overwelms C2 such that C2 ESR changes don't matter much.]
-
'Original' caps: Capxon KF 1200uF 16v
ESR = 0.061ohm
Max rated Ripple Current = 1500mA

Assuming 80mV Ripple @100kHz from power source.
[ATX spec is 120 mV on +12v and a screen's basic PSU isn't going to be that good so 2/3 of the ATX spec is a conservative value.]

Will be looking at C1 only as the current through C2 won't change much with the relatively high impedance of the coil in series with it.

C1 branch with KF installed and 80 mV Ripple from power source.
0.061 ohm --> 1311 mA Ripple through C1.
[186 mA less than the KF's max Ripple Current rating.]

Now you blindly replace the KF with an FM of the same uF/volts because you are too lazy to do the math.

'Replacement' cap: Panasonic FM 1200uF 16v
ESR = 0.018ohm
Max rated Ripple Current = 2470mA

C1 branch with FM installed and 80 mV Ripple from power source.
0.018 ohm --> 4444 mA through C1.
1974 mA MORE than the FM's rated max Ripple Current.

Congrats!
Your plan has resulted in exceeding your pet FM's max Ripple rating by almost 2 amps.
In fact: The FM's max Ripple Current rating would be exceeded with only 45 mV of Ripple present.

- So, in effect, the much lower ESR 'good' cap can only handle about 1/2 the ripple of the crap cap without overheating and degrading itself.

So I'll repeat the standard recommendation that -responsible- techs hand out to people that could otherwise get into trouble:
---- - IF YOU AREN'T GOING TO DO THE MATH, then stick as close to the original values as possible.
.
.
.

[PCBONEZ]

Re: Samsung SyncMaster 215TW crappy caps

On the other hand, voltage is specified as a 'better than' value - after a suitable aging period, the capacitor will withstand that voltage forever. It does not say the capacitor will not withstand a higher voltage.

.
Actually it says EXACTLY that they can NOT withstand higher voltage if you bother to look up what the voltage rating means where it is written, which is NOT in the data sheets.
- The data sheets assume you know what it means because it's so BASIC that anyone looking in a data sheet should already know - so they don't explain it there.

According to Chemicon: You are wrong:
---
Rated Voltage:
If the applied voltage exceeds the rated voltage of the capacitor, the capacitor may be damaged from an increase in leakage current. When using a capacitor with an AC voltage superimposed on a DC voltage, care must be exercised so that the peak value of the AC voltage plus the DC voltage does not exceed the rated voltage.
---
http://www.chemi-con.com/index.php?o...id=8&Itemid=21

According to Panasonic: : You are wrong: [Those people that make the FMs you like]
---
(2) Applied voltage: Do not apply an excessive voltage (voltage exceeding the rating). The peak direct current voltage superposed with a ripple voltage (alternating current component) must be equal to or less than the rated voltage. A surge voltage exceeding the rated voltage is allowed and specified. However, the allowable conditions are limited and the specifications do not guarantee the application of such a surge voltage for a long time.
---


According to Rubycon: You are wrong: [All be it a rather wimpy warning.]
---
4) APPLIED VOLTAGE
Do not exceed the rated voltage of capacitors.
---


According to Nichicon: You are wrong:
---
2-3-3 Excess Voltage Application:
As Fig. 2-4 shows, the leakage current rises sharply when voltage above the rated voltage is applied.
When the withstand voltage of the anode foil decreases due to the generation of heat and the anode foil undergoes
insulation breakdown, a large amount of current will flow through and cause the internal pressure to rise within a
short period of time. If the pressure relief vent is activated, the electrolyte that has changed to gas is vigorously
released from the opened vent. The energy of the capacitor is proportional to the second power of the
voltage . Therefore, the higher the applied voltage, the more severe the condition of the activated
vent, and the more likely that a short between the foils will occur.
- Please use capacitors within their rated voltage.
---
https://cdn.badcaps-static.com/pdfs/...64fb172f94.pdf
~~~~~

~~~~~
4 out of 4 major manufacturers I checked say your voltage theory is DEAD WRONG in their tech docs and specifically warn against it.
[Although I didn't need to check to know that, just to find the links.]
~~~~~~
In fact most of the crap brands have warnings about exceeding the rated voltage.
The voltage rating info has NEVER been elusive and is very easy to find.
It's VERY BASIC knowledge and probably covered in the first DAY on Capacitors in any electronics course.
.

[PlainBill]

Re: Samsung SyncMaster 215TW crappy caps

.
The accuracy of the common Bob Parker based ESR meter is +/- 1 digit [plus] +/-5%.
So your .02 ohm reading could have easily been actual value .03 ohms +5%.
And that's only if the meter it was accurately calibrated and the battery up to par.
.
While it's reasonable to expect the ESR to be de-rated to some degree to ensure it doesn't go out of spec in use,
It is NOT reasonable to assume it's de-rated markedly.
It is NOT reasonable to assume the degree of de-rating of a good brand is different than the degree of derating of a bad brand. [They do that the same way for the same reasons.]
<SNIP>
.

Blah, bla-blah, blah, blah, blah.

Once again you rattle on, citing figures, and baseless speculation.

Define 'Markedly'. You love the term, please define it.

Exhibit 'A' A new 220uF, 25V Panasonic FM cap, and a freshly zeroed ESR meter. The rated impedance - .056 ohms. The measured ESR - .02, less than half of rated. As far as your 'Sell it as higher rated' - they CAN'T. Unless Panasonic has some secret ultra-low ESR series, FM is as good as they go.

Next, what is going to be the consequence of using lower ESR caps? Well, obviously higher ripple current. Could that damage the SMPS? Not likely, they have current limiting on the primary. And the other result - lower ripple voltage. OHHH, big danger there - the power rails will have less noise on them.

As far as the cheap Chinese manufacturers following the same standards as the more reliable Japanese manufacturers, that's real funny.

Now internet etiquette insists that at this point I tell you to "Shut up", 'Don't comment on my posts", "Don't quote any of my posts", "Don't read any of my posts", and other childish nonsense. Sorry, I'm more mature than that.

You are welcome to read, quote, and comment on any of my posts. You can call me anything you want, you can drag out any long winded proofs you desire. I don't care! Heck, I WELCOME it. As a matter of fact, I would REALLY welcome your giving advice BEFORE I do. It'll save me time.

And at the end of the day I will be content, knowing that my advice will get monitors and TVs fixed with the least stress possible.

PlainBill