Swap a 1000uf 10V for a 1500uf 16V

[PCBONEZ]

Re: Swap a 1000uf 10V for a 1500uf 16V

Please remark on my choice of replacements, detailed elsewhere on this thread, if you would.

I can't without knowing the series, uF, volts, and physical size of the originals.
Capxon makes many different series of caps and the specs vary widely from one series to another.
.

[Junkrepair]

Re: Swap a 1000uf 10V for a 1500uf 16V

My 19MF337B repair is a success so far. Here are the caps I chose as replacements for the three bad capXons (references C112, C117, and C118 on the circuit board):



Panasonic/ECG
EEUFR1C102
P14398

Category Capacitors
Family Aluminum
Series FR
Capacitance 1000uF
Voltage Rating 16V
Tolerance ±20%
Lifetime @ Temp. 8000 Hrs @ 105°C
Operating Temperature -40°C ~ 105°C
Features General Purpose
Ripple Current 1.79A
ESR (Equivalent Series Resistance) -
Impedance 28 mOhm
Mounting Type Through Hole
Package / Case Radial, Can
Size / Dimension 0.394" Dia (10.00mm)
Height 0.630" (16.00mm)
Lead Spacing 0.197" (5.00mm)

The only 1000uF caps I found on the radioshack site were rated for only 85 degC, which seemed like a bad idea since the original capXons were rated 105 degC and had blown their tops. Since the capXons were marked LZ, I hope the 28 mOhm impedance is low enough.

The replacements are about 2mm taller than the originals, which were about 14mm tall (before they popped). I couldn't tell exactly how tight the new fit is, but it was easy enough to reinstall the metal cover over the circuit board. The other dimensions are the same as those of the bad caps.

I hope my solder work was adequate. When desoldering, I must have gotten a little rough with the braid and accidentally scrubbed the shiny little circle of electrical trace from around one of the through holes. But I think i got a connection from some solder down in the hole since the lead is not easily pulled out. Anyway it works so far.

Remarks are welcome.

One question I have is whether the three original caps went bad just because they were poor quality or maybe because of some deficiency in the design.

[PCBONEZ]

Re: Swap a 1000uf 10V for a 1500uf 16V

Okay, something isn't getting across here.
Need to know specs on the OLD caps before I can compare anything.

I gather these were Capxon LZ series.
What uF, volts, diameter were they?

http://www.capxongroup.com/en/prod_all_cat_full.aspx

.

[PCBONEZ]

Re: Swap a 1000uf 10V for a 1500uf 16V

The only 1000uF caps I found on the radioshack site were rated for only 85 degC, which seemed like a bad idea since the original capXons were rated 105 degC and had blown their tops.

Radioshack does not sell low ESR caps.

Since the capXons were marked LZ, I hope the 28 mOhm impedance is low enough.

FR have good ratings for ESR & Ripple so you should be okay,,
but as I said I can't know for sure without an ID on the old caps.

You'll get better at soldering. I does get easier..

One question I have is whether the three original caps went bad just because they were poor quality or maybe because of some deficiency in the design.

Poor materials + poor QA. [Quality Assurance]
Chinese made Aluminum is less pure and has different impurities than Japanese or US Aluminum.
Some of those impurities cause the electrolyte to break down and form gasses inside the can.
It is basically the same failure as the 'stolen electrolyte formula' fiasco a few years ago but it is slower because it takes time for the impurities to leach out of the Aluminum can and foil.
Heat and more 'ESR aggressive' electrolyte formulations tend to exacerbate the problem.
-
In so far as QA the CH and TW companies [depending on which] either don't have any at all or don't have adequate programs/procedures.
[This is in general...]
A Japanese company will test materials when they receive them to ensure they got what they ordered.
A CH or TW company is more likely to assume they got what they ordered and not test anything. Even when they do test they might not test thoroughly.
.

[Junkrepair]

Re: Swap a 1000uf 10V for a 1500uf 16V

Okay, something isn't getting across here.
Need to know specs on the OLD caps before I can compare anything.

I gather these were Capxon LZ series.
What uF, volts, diameter were they?

http://www.capxongroup.com/en/prod_all_cat_full.aspx

.

I believe I probably have the same model HDTV as the OP's,
I have the same markings on my three bad caps as the OP's had on his one bad cap:

10mm diameter x 14mm tall
black with gold lettering
markings:
capXon
1000uF
10V
P727
LZ 105 degC
VENT

I guess I was asking for a probabalistic answer, hoping that the replacements I chose had specs consistent with a very wide range of applications. But I will try to get specific by following the links you provided and trying to find the exact specs of the bad caps.

[PCBONEZ]

Re: Swap a 1000uf 10V for a 1500uf 16V

Okay those are 10x12.5mm Capxon LZ.
[The 14mm you got is due to the space under them.]
Ripple is 1500 mA and ESR is .027 ohms.

The caps you used [taken from your post] are 1790 mA Ripple and .028 ohms ESR.
You did very well.
.

[Junkrepair]

Re: Swap a 1000uf 10V for a 1500uf 16V

Need to know specs on the OLD caps before I can compare anything.

http://www.capxongroup.com/en/prod_all_cat_full.aspx

.

Okay, I did not find a 10mm x 14mm cap in the capXon data, but there follows the closest match (your second link above) I found of an online capXon spec to the bad capXon caps removed. I also compare that closest match to the spec of the Panasonic replacements I used.

best-match capXon spec vs. replacement cap spec
=============================
capXon -- Panasonic
series LZ -- series FR
10mm x 12.5mm -- 10mm x 16mm
model? -- model EEUFR1C102 aka P14398
1000uF -- 1000uF
10V -- 16V
2000 hrs@105 degF -- 8000 hrs@105 degF
1.5 A ripple -- 1.79 A ripple
27 mOhms Z -- 28 mOhms Z
25% tolerance -- 20% tolerance

[Junkrepair]

Re: Swap a 1000uf 10V for a 1500uf 16V

Okay those are 10x12.5mm Capxon LZ.
[The 14mm you got is due to the space under them.]
Ripple is 1500 mA and ESR is .027 ohms.

The caps you used [taken from your post] are 1790 mA Ripple and .028 ohms ESR.
You did very well.
.

Thank you.

I was attracted by the 8000 hr life and the name brand of the model I chose. I was worried about the higher ripple, but that, as you explained, was an improvement too.

[Junkrepair]

Re: Swap a 1000uf 10V for a 1500uf 16V

You'll get better at soldering. I does get easier..
.

I've soldered pretty much over the years, but mostly stuff like splicing wires and sweating copper pipes. Haven't done much work on circuit boards though.

I guess the metal trace on the board is supposed to coat the whole inside of the through-hole. Or at least I hope so, as there was not much left of the metal ring around the hole after I got rough with the desoldering braid.

[PCBONEZ]

Re: Swap a 1000uf 10V for a 1500uf 16V

Surprising that usually happens when the iron doesn't get hot enough.

You want real hot for short time so the solder melts and you can 'get off' before the heat has time to to 'soak' deeply into the PCB.

[Junkrepair]

Re: Swap a 1000uf 10V for a 1500uf 16V

Surprising that usually happens when the iron doesn't get hot enough.

You want real hot for short time so the solder melts and you can 'get off' before the heat has time to to 'soak' deeply into the PCB.

I had removed the bad cap and was trying to draw the old solder out of the hole by poking the braid partly into the hole using the tip of the iron. I think I rotated the braid, thus scrubbing the metal ring from around the hole. That was on the underside of the board, not on the component side. I don't believe there was by design any conductor trace leaving the hole on the underside---only on the component side, in other words, just one conductor trace going to each terminal of the cap, both traces being on the component side. Not sure I am using standard terms and explaining clearly.

[PCBONEZ]

Re: Swap a 1000uf 10V for a 1500uf 16V

I understand.
What I am trying to get across is that if you apply heat too -long- the PCB material [under the pad] starts to melt and that is when the pads come loose.
-
With much heat on top for a short time you can melt the solder fast enough to not heat the PCB much.

Without getting into fancy tools the best way to clear holes is to use a SS needle just smaller than the hole [but bigger than the cap leads] on one side while heating the other side until the needle sides through.
The solder won't easily stick to SS so getting the needle back out isn't too rough.

You will need a holder because the needle will get hot.
I like an [all metal] exacto knife handle for a holder.
Some people use chunks of terminal strips but that looks like a good way to burn your finger tips to me. [Granted I haven't actually it tried that way...]

The holes have 'vias' which basically means they are plated all the way through.
Some electrical connections are made to the via between layers of the PCB.
[Especially common practice on the ground lead of a cap.]
If the pad is gone there is a risk of not getting a connection to anything between the PCB layers due to melted PCB material contaminating the solder in the hole.
-
Sounds like you got it working, just saying why it matters.
.

[Junkrepair]

Re: Swap a 1000uf 10V for a 1500uf 16V

I understand.
What I am trying to get across is that if you apply heat too -long- the PCB material [under the pad] starts to melt and that is when the pads come loose.
-
With much heat on top for a short time you can melt the solder fast enough to not heat the PCB much.

Without getting into fancy tools the best way to clear holes is to use a SS needle just smaller than the hole [but bigger than the cap leads] on one side while heating the other side until the needle sides through.
The solder won't easily stick to SS so getting the needle back out isn't too rough.

You will need a holder because the needle will get hot.
I like an [all metal] exacto knife handle for a holder.
Some people use chunks of terminal strips but that looks like a good way to burn your finger tips to me. [Granted I haven't actually it tried that way...]

The holes have 'vias' which basically means they are plated all the way through.
Some electrical connections are made to the via between layers of the PCB.
[Especially common practice on the ground lead of a cap.]
If the pad is gone there is a risk of not getting a connection to anything between the PCB layers due to melted PCB material contaminating the solder in the hole.
-
Sounds like you got it working, just saying why it matters.
.

Oh yeah, "pads" and "vias". I knew those words a couple years ago when I was designing a circuit board. I never did build it though.

Thanks for the tips. I'll remember to use a stainless pin next time I have to clear solder from a hole.

Thanks again for all your helpful replies.

Kurt

[billy66]

Re: Swap a 1000uf 10V for a 1500uf 16V

I just found one of these Philips 19mf337b next to a dumpster. Opened it up and caps were blown... replaced and now it works. Only problem is that the screen is damaged. Looks like the TV must have went bad, and then the owner took out his/her frustration on the screen. It is a shame. Makes me want to put up signs all over town "If your LCD TV/Monitor stops working, please just give it to me instead of breaking it more in frustration or throwing it out".

[retiredcaps]

Re: Swap a 1000uf 10V for a 1500uf 16V

I just found one of these Philips 19mf337b next to a dumpster. Opened it up and caps were blown... replaced and now it works.

Maybe you can sell the boards on ebay to make a bit of money?

[billy66]

Re: Swap a 1000uf 10V for a 1500uf 16V

Maybe you can sell the boards on ebay to make a bit of money?

Not a bad idea. I don't really do this for the money though. I'm not sure the hassle is worth it to be honest. I have an electronics recycling place around the corner from me. They pay $2/lb for computer boards. I will just add it to my pile. I take a box full there every so often and they sell me LCD monitors for $10 a piece.

I get more joy out of fixing the broken monitors and then selling them very cheaply. I really don't make money... just enough to support my hobby and maybe buy a case of beer each month.

On another note, if someone on this forum needs this board, or the power supply to this monitor... I'd be willing to ship it with the original caps on it... for the cost of shipping.

[cadillacman]

Re: Swap a 1000uf 10V for a 1500uf 16V

ESR / Ripple

1000uf 10v Capxon LZ Series 8x16mm : 0.029 / 1450
1000uf 10v Capxon LZ Series 10x12.5mm : 0.027 / 1500

And the winner is -> 1000uf 16v Panasonic FM 10x16mm : 0.026 / 1790
-
Slightly better ESR and better ripple without changing the uF.
.

and a higher voltage rating too.. should be a little tougher...

[PCBONEZ]

Re: Swap a 1000uf 10V for a 1500uf 16V

Nice thought but it doesn't work like that.

The voltage rating is based on the thickness of the aluminum oxide layer which is the actual dielectric.
In use the thickness of the oxide layer will adjust to a value constant with the applied voltage.

You could put one each 16v, 10v and 6.3v caps in parallel on [an actual] 5 volts and within a few hours they will -all- effectively be 5v caps.
.
That's one of the reasons re-using lytic caps is a bad idea.
.

[PlainBill]

Re: Swap a 1000uf 10V for a 1500uf 16V

Nice thought but it doesn't work like that.

The voltage rating is based on the thickness of the aluminum oxide layer which is the actual dielectric.
In use the thickness of the oxide layer will adjust to a value constant with the applied voltage.

You could put one each 16v, 10v and 6.3v caps in parallel on [an actual] 5 volts and within a few hours they will -all- effectively be 5v caps.
.
That's one of the reasons re-using lytic caps is a bad idea.
.

That sounds like the subject for a high school science project, and it's relatively easy to demonstrate. There are plenty of monitors that have plenty of room on the power supply for a larger cap. Measure the leakage current of a 10V electrolytic cap at it's rated voltage. Solder it in place, run the monitor for a few days, pull the cap and measure the leakage current at rated voltage again. Substitute 25V, then 63V caps, repeating the process for each.

PlainBill

[cadillacman]

Re: Swap a 1000uf 10V for a 1500uf 16V

somebody do that you have my curiosity peaked.