Sitecom WL-341 with bad Teapo SY

[marcus905]

Well

I had this router for free from a friend (the unit is a rebadged Sercomm IP1006RRv2.)

He bought another one when this router kept freezing randomly soon after being turned on. The router was fairly new but he didn't have a receipt so he gave it to me and I took it apart to try to see if fixing it was possible.

In the pics there's what I found:

4 Teapo capacitors:
3x SY 470µf 16v (8x15mm 3.5mm terminal spacing) that look fine
1x SY 330µf 10v (6.3x11mm 2.5mm terminal spacing) that is bulged

Neither is listed in Teapo's datasheet for the SY series.

Since a couple of the boards I used had the same problems when their capacitors bulged or vented and I recognize Teapo as a cRapacitor manufacturer, I proceeded to remove all the capacitors.

Now I'm asking for your help in choosing the right replacements, maybe getting some with better specs as the router should stay on 24/7 reliably.

The power/voltage regulation circuitry is based on 2x MP9141ES ICs and the external wall wart PSU outputs 12VDC 1A.

Thanks in advance!

[Th3_uN1Qu3]

Re: Sitecom WL-341 with bad Teapo SY

I personally don't think it's those Teapos at fault. Put them back in and run the router on a PC power supply and see if it still locks up. If it does not, pop open the wall wart and see what's in there.

[marcus905]

Re: Sitecom WL-341 with bad Teapo SY

I don't have a PC PSU available at the moment... I measured the wallwart output with a multimeter and with no load it outputs 13.4V.

In your opinion is the bulged Teapo good and I can put back that too, or I should replace at least that one?

Anyways I'll try to pop the wall wart open... any suggestion on how to do it as it's sealed and has no screws?

Ill try to see if I find a regulable output wallwart to try with that instead of the PC PSU now

EDIT: I tested the bulged cap with an ohmmeter and it never gets to infinity, but settles in 5 or so seconds to 1.7Mohm while the others climb very slowly, like 1.5Kohm/sec.

EDIT2: I couldn't repeat the ohmmeter phenomenon with the bulged cap so disregard it, it may have been a fluke or a misreading on my part.

[Th3_uN1Qu3]

Re: Sitecom WL-341 with bad Teapo SY

Didn't notice the bulged cap, thanks for pointing it out. Of course, replace that one. That cap is likely on the logic rail... hmm, the wall wart may not be bad in that case. Just a second, let me look for a replacement. Edit: This. Some extra capacitance won't hurt, as long as it fits. They likely went with the bare minimum required, so a step up does not hurt.

For the wall wart, you'll have to be creative. There was a thread on that over here IIRC. But replace the bulged cap first. I'll have to be more careful when reading stuff next time... guess i have too many things on my mind ATM.

[kc8adu]

Re: Sitecom WL-341 with bad Teapo SY

replace them all now or one at a time later.
check the wallwart too if its a lightweight switcher type.
looks like a netgear i did a while back.panasonic fm is a good choice.

[marcus905]

Re: Sitecom WL-341 with bad Teapo SY

Didn't notice the bulged cap, thanks for pointing it out. Of course, replace that one. That cap is likely on the logic rail... hmm, the wall wart may not be bad in that case. Just a second, let me look for a replacement. Edit: This. Some extra capacitance won't hurt, as long as it fits.

It's bigger than the one that was there (it's 8x12 - pitch 3.5, while the one that was there is 6.3x11 - pitch 2.5,) I don't know if it fits. I found some Rubycon ZLH 10v 330uF locally, would those be good?

Since I've desoldered all of them already, what could be some alternatives to the other 3 Teapos? And some alternatives for the bulged one other than the Rubycon ZLH I found?

They likely went with the bare minimum required, so a step up does not hurt.

For the wall wart, you'll have to be creative. There was a thread on that over here IIRC. But replace the bulged cap first. I'll have to be more careful when reading stuff next time... guess i have too many things on my mind ATM.

I found an alternative PSU: a Seagate expansion I have uses a compatible PSU.
In case, if after replacing the capacitor it still freezes, I'll try with this one.

[jsog]

Re: Sitecom WL-341 with bad Teapo SY

Since you have them out anyway, might as well replace them with something better. Especially that bloated one, which is hard to see in the photos. All I can find of the Teapo SY series is "long life, low impedance". I would lean towards Panasonic FR for the life/temperature rating, or FM.

Some switcher wall warts are repairable, most are not worth it. Try another.

[Th3_uN1Qu3]

Re: Sitecom WL-341 with bad Teapo SY

I found some Rubycon ZLH 10v 330uF locally, would those be good?

Yes.

[marcus905]

Re: Sitecom WL-341 with bad Teapo SY

Well, the ZLH weren't available anymore when I tried to get them at a local shop; I think I'll have to order them online (but when you buy only a few units the shipping is too much :/)

[OT]
BTW, I tried to get a friend to buy those for me at another store instructing him to avoid buying crap, and this is what he brought me... I think it's the first time I see those capacitors, and judging from the datecode NOS is an euphemism in this case! Moreover it's probably the first time I saw a Philips capacitor!
[/OT]

[Th3_uN1Qu3]

Re: Sitecom WL-341 with bad Teapo SY

Those are good caps if you're dropping them in a piece of analog gear, not a SMPS or a CPU bypass. Don't let the age fool you - they are high quality parts, and even after all those years they likely drifted less in value than crapcaps do in an year... They're just not suited for your application.

[marcus905]

Re: Sitecom WL-341 with bad Teapo SY

Yeah, I know... I saw ELNAs in high quality amps so I knew them, but I was surprised to find 24 year old ones still in shops they probably just need to be slightly reformed

I don't seem to find the Philips 035 datasheet anywhere also.

I'll see where I can get the ones I need.

Thanks again

[PCBONEZ]

Re: Sitecom WL-341 with bad Teapo SY

When a data sheet doesn't have an exact cap use the closest one with the same physical can size.

3x SY 470µf 16v (8x15mm) 840 mA, 0.087 ohms.
1x SY 330µf 10v (6.3x11mm) 340 mA, 0.220 ohms.

Cross references to Chemicon KY and Nichicon HE.
[So those or better would do fine.]
.

[marcus905]

Re: Sitecom WL-341 with bad Teapo SY

After a long local search, a soldering mistake, a burnt finger from the soldering iron and lots of swears because I'm not used to clipping the leads at the right size (and I mean lots) I finally managed to repair the unit using Rubycons. I used a ZLJ for the smaller 10v330u and MCZs for the 16v470u. Now the unit seems to be working fine but I'll leave it on overnight to see if it keeps going.

To be honest, the first poweron scared me a lot as the unit needed about 30 seconds to 'warm up' before starting at all but now it seems to be going fine. I'll post a picture of the completed work later so that you can judge the quality of my work (a double first: first time recapping and first time using a soldering iron.)

I'm going to start another thread soon as an el-cheapo chinese external tray PSU fried and needs a recap + a new fuse too.

Thanks again for all the help

[marcus905]

Re: Sitecom WL-341 with bad Teapo SY

Pictures

Judge my double first

I forgot to mention I mounted a pinheader too and that's the reason for those solder balls. I figured out that more solder there = more mechanical resilience.

There you go!

PS: those yellow/brown burned material splotches are from the excess solder resist/flux/coating that is still on the board.

Another thing: is it normal for the caps to be a little bit hot to the touch, maybe 45°C, with the router operating?

Thanks again!

[PCBONEZ]

Re: Sitecom WL-341 with bad Teapo SY

Looks like a good job!

45°C sounds about right if there's a lot of Ripple getting filtered out.
Might wanna make sure the thing has good ventilation.
Maybe mount it on edge or at a steep angle so heat can flow in from a low vent and exit through a high vent by natural circulation.
[Or you could go nuts and add a small low amps fan. That -could- cause EMI issues though.]
.

[marcus905]

Re: Sitecom WL-341 with bad Teapo SY

Looks like a good job!

Thanks!

45°C sounds about right if there's a lot of Ripple getting filtered out.

Actually I took the time to measure the temps on those caps: after 6 hours of light use the MCZ were around 52°C on average (55, 53, 46) and the ZLJ was at around 38°C

Should I crack the wallwart open too to see if there's something wrong with that?

[Th3_uN1Qu3]

Re: Sitecom WL-341 with bad Teapo SY

Temps look alright to me. I've seen motherboards that ran the caps hotter than that, so you should be fine.