Another Tagan, this time with failed Panasonic...

[robert]

Just got yet another unstable pc with a tagan PSU.
This time the psu seems to be cooked even more, even the 2 Panasonic TS-UP 470uF/200V primary caps are bloated!
Never saw anything like that.
Fans both are okay, computer doesnt run that hot (rather powerful 120mm fan on the back side) so why?

Usual Tagan build quality and board cleaning:


Now for the Panasonics:

[370forlife]

Re: Another Tagan, this time with failed Panasonic...

Typical ill-designed topower.

[i4004]

Re: Another Tagan, this time with failed Panasonic...

dirty mains?
lightning strike nearby?
running off the inverter (UPS or 12->220V converters) for prolonged periods?

primaries usually don't go out on their own even when they're crappy quality.
let alone when they're pana.

[robert]

Re: Another Tagan, this time with failed Panasonic...

That place runs a few PCs with Enermax PSU with no trouble, as well as a huge load of macs, again with no trouble expect for one G5 blowing up within warranty (replaced with no trouble).

Mains power is fairly okay (after the neutral connection broke some years ago, destroying lots of electronics with 400V across them then, everything was re-done properly) and as far as i know, they only have their servers on a UPS, and these run some NMB PSUs which are known to be close to indestructable (and weigh 3 times as much as any enermax).

The PSU is well-loaded however (Athlon 64, Geforce 6600GT) for a 330W unit, though that shouldnt blow it that quickly.

What i could imagine would be that the dirt on the PFC board caused leakage on the wrong (right) place (voltage feedback resistors), increasing the DC bus voltage beyond 400V. Didnt measure anything there before taking the PSU apart and cleaning it.

Im going to repair that PSU, Secondary side with Pana FM aand Rubycon ZLG, Primary Pana TS-ED (their highest spec type, 105°C 3kh), anything wrong with that?

[i4004]

Re: Another Tagan, this time with failed Panasonic...

you have a-pfc there, and still 2 caps are used?
mhm....

yes, your explanation about goo on pfc board making trouble makes sense.

as for replacements, you should aim to have same esr as prev. caps had.
putting ultra low esr caps where gps were doesn't need to be too good idea esp. on psus.

because of such things
http://www.jonnyguru.com/modules.php...rint&ndar_id=8

[370forlife]

Re: Another Tagan, this time with failed Panasonic...

you have a-pfc there, and still 2 caps are used?
mhm....

yes, your explanation about goo on pfc board making trouble makes sense.

as for replacements, you should aim to have same esr as prev. caps had.
putting ultra low esr caps where gps were doesn't need to be too good idea esp. on psus.

because of such things
http://www.jonnyguru.com/modules.php...rint&ndar_id=8

As I said, another ill-designed topower. Add-on APFC board dosen't agree with model designed for PPFC.

Only other manufacturer I have seen use a add-on APFC board is leadman.

[robert]

Re: Another Tagan, this time with failed Panasonic...

Yep, the main PCB contains a place for a bridge rectifier, which, in non-EU models, contains one, too.
Here, 4 wires are soldered to it, that go to the PFC Board, that isnt so bad compared to other PSU i have seen (it doesnt blow up right away, so it is).
Oh, the sec side contains some ugly crap:
+5V rail goes from the rectifier trough the storage inductor, 3300u, small filter inductor, 3300u, just as usual.
But +12V: rectifier - storage inductor - smaller inductor - 2200u
No capacitor after the storage inductor.
This is a fairly large screw-up, because the added inductance not coupled to the other rail worsens cross regulation.

3.3V are not regulated by the ususal saturable reactor (i hope correct translation to "Transduktor" in german) but this time, is produced by a step-down switching regulator, fed off the +5V.
+5V from the storage inductor is filtered by a small inductor, 2200u (16V!) to the input of the stepdown regulator. After its storage inductor, theres a 2200u 10V, a small filter inductor, and another 2200u 10V.
Now interestingly, these 3 caps are CE-WH type (green), while all other are CE-WR (black).
The 2200u/16V unit at the input of the stepdown switcher will recieve some ugly ripple current here.
No datasheet as usual.

So this is essentially an AT PSU with a standby PS and 3.3V "glued on".

Yes, very low ESR capacitors can sometimes result in trouble, this usually indicates bad PSU design when the control loop gets instable. Can be fixed, but im gonna see.

BTW, why is it so hard to get GOOD PSUs in the 200-400w range?
I never assembled a PC that draws more than 250W (most are <150W) off the AC line in any case, so i dont need all these 800W+ units. Just high quality, long life, low noise 250W.

I guess i have to design my own one some day...
(im an EE, doing consulting work mostly to customers whose names should not be disclosed in products that usually include low voltage SMPS, but i rarely ever do off-line PSU design. Also putting together PCs for a few friends and related companies when theres little other work.)

[i4004]

Re: Another Tagan, this time with failed Panasonic...

>BTW, why is it so hard to get GOOD PSUs in the 200-400w range?

it's not so hard, damn it.
i get fortron all the time for 30 or so EUR and they're built like a fuckin tank.

they have a sweet +5vstby circuit, they have decent caps(teapo and sometimes ost) which can last a lot in such designs, and they're well cooled, with a big fan.
there's equally nothing wrong with the control ic, and the protections it has, or any other thing, for that matter.

https://www.badcaps.net/forum/showth...hlight=fortron
https://www.badcaps.net/forum/showth...ht=fortron+350

i said "damn it" because i noticed you spat on fortron and seasonic last time.
which you offcourse have the right to do, but you should at least give model numbers and years of mfr.
(yes, fortron did have a bad design or two some time ago...example here:
https://www.badcaps.net/forum/showpo...0&postcount=36
that fortron is crap...but to say all fotrons are...is rubbish in itself)
these days, seasonics are probably amongst best makes overall, and fortron is a "budget" make which i read as "best psu for the lowest amount of money", as cheaper psus are chinese crap, and more expensive are hi-watt overkill.
(offcourse, fortron makes more expensive models too...but for me it's a cheapest psu with good quality...and yes, it's still more expensive than chinese crap...and yes, some will still say "why the hell did you pay psu so much?")

so if you pick any of those 2 fortrons i mention, i can gurantee you have a good and reliable psu.
they can probably outlive the pc they're in.

also, once you start to look for decent +5vstby circuits, you'll soon relize you can go cheaper than fortron, but you'll probably have to recap such psu to trust it fully for extra long periods.
as they may come with asia-x and simillar caps, which in itself, doesn't mean they'll destroy the mobo(because +5vstby crap dpes that), but just that they probably won't last as psus with better caps.
but even THAT way they can probably last quite enough from user's perspective, because when i remember how much crap have i seen that did more than 5-6 years...oh gosh....and most didn't even have 12cm fans most todays have etc.
so overall, no, situation is not that bad.
only yes, you need to inspect its +5vstby corcuit to be sure.
but you can usually do that just by lookin thru the fan grille, so there....not that hard to find something that won't blow the mobo etc..

and if you want something better, get corsair 450w.
it should have all japanese lytics.
myself.......i don't need all jap lytics in my psu...
i like all polys on my mobo, though.
http://asus.com/product.aspx?P_ID=ILTh1fZDCOAEjPcB
<wink>

[japlytic]

Re: Another Tagan, this time with failed Panasonic...

The Panasonic UP Series has a minimum rated life of 3000 hours.
As I said elsewhere, even the best units are not immune from failure.
Typically, I would specify electrolytics with a temperature rating of 105C or higher.

[c_hegge]

Re: Another Tagan, this time with failed Panasonic...

85*C caps are quite common as PSU Primaries. It's still unusual for them to fail. I often see Antecs several years old with good Fuhjyyu primaries (although the secondaries are usually toast).

[stj]

Re: Another Tagan, this time with failed Panasonic...

a leaky (not shorted) rectifier diode will heat and damage the primary caps.

[Oklahoma Wolf]

Re: Another Tagan, this time with failed Panasonic...

BTW, why is it so hard to get GOOD PSUs in the 200-400w range?

Because expensive 300 watters don't sell

[robert]

Re: Another Tagan, this time with failed Panasonic...

My experience with Fortron is mostly around older ones (ie up to around 2004).
At that time, they were full of Fuhiyyu and sometimes didnt even survive long enough to blow them up.
Similar things with Seasonic.

The worst of all were OEM models made for Maxdata, and Medion/Tevion.
Delta also made OEMs for Medion, which sucked (full of Ltec and GSC, which promtly blew up after 2 years), while the "same" type number OEMd for Compaq had Chemicon and Rubycon in there...

This was a Fortron (or possibly Seasonic), i dont know which model that was, but something around 250W:


Yep, vaporised the entire transistor lead, without blowing the fuse...
GREAT stuff.

Tagan at least uses an 3842 for the standby PSU (i would never even think about buying a PSU that uses the 2-transistor-design, knowing how these fail, and how often they do as i see lots of these blown up).

Still had the caps on +5V stby completely blown (ESR 10R for the first one (blown open) , and >20Ohm for the second one (not bulged much!) after the filter.
+5V has both caps with 2-3Ohm ESR, the other ones surprisingly are all below 100mOhm.

[i4004]

Re: Another Tagan, this time with failed Panasonic...

>Tagan at least uses an 3842 for the standby PSU

you're still thinking in the terms of the past.
fortrons i mention use dm311.
(although 3842 is usually found as main pwm ic, not the +5vstby primary circuit...+5vstb with it would be too complex, afaik...there are better and simpler solutions, like mentioned dm311, or topswitch etc.)

also, you're aware that tagan doesn't make psus at all, right?
they source from other mfrs, and typically crappy ones, by the look of things.
they just put their badge, and offcourse, the mile-high price...

afaik, fortrons i mentioned (fortrons of today) are airplanes for this tagan-branded crap you described in your last 2 threads about them.

so yes, i believe fortron has made mistakes in the past, and there are probably even still some sparkle models with crappy +5vstby. but if you think all fortrons are still crap, you need to think again.

oh yeah, delta is good too.
i have 3-4 years delta(chieftec) at my nieces' pc, and it's excellent design and reliability.
again, i dunno how were they in 2004.

but if all psus were like fortron, seasonic and delta of today there would be no much need to replace or repair psus.

[370forlife]

Re: Another Tagan, this time with failed Panasonic...

If you need good quality 300-400W psu's, hop onto ebay and find some OEM delta's for cheap.

Enlight and some chieftec's (most are sirtec...bleh) are delta also.

As far as FSP goes. Ehh. There are better ones out there I can get for cheaper. I don't know where i4004 gets his godly FSP's, but The ones I have worked with were so-so.

[i4004]

Re: Another Tagan, this time with failed Panasonic...

>As far as FSP goes. Ehh. There are better ones out there I can get for cheaper. I don't know where i4004 gets his godly FSP's, but The ones I have worked with were so-so.

you know 370 i would like to contest everything you said here, in this manner:
first of all what fortron models of recent production, say last 2-3 years, have you dismantled, and what did you see inside to make you say you can get better for cheaper?

to that extent, what is the better psu you can get for cheaper, but no ebay deals, please. let's take this outside smuggler's realm and deal with something you can buy in shop and get full warranty for.
(i would also like to see pics of those better ones you can get cheaper AND pics of those fortrons that are not so good by your judgment)

oh yeah, i said what fortron models i inspected, didn't i?

now you tell us which models you inspected.

and all this because you make it seem that fortron is crap in usa, while we had many members saying they're using fortron for years without issues.

oh yeah, sparkle is not fortron, afaik.

and yes, this one
http://www.newegg.com/Product/Produc...82E16817104045
should be fairly simillar to the models i described, by the look of things.
and those sagas looks ok too.
(offcourse i didn't inspect these from inside so it's just a guess...)

[Oklahoma Wolf]

Re: Another Tagan, this time with failed Panasonic...

oh yeah, sparkle is not fortron, afaik.

Sparkle is Fortron... FSP bought them up years ago.

This was a Fortron (or possibly Seasonic)

FSP - the transformer markings are a dead giveaway.

[i4004]

Re: Another Tagan, this time with failed Panasonic...

>Sparkle is Fortron... FSP bought them up years ago.

i know that, but i added "afaik" exactly because of it.
sparkle is still sparkle for me...notice this (see the sticker)
http://tinyurl.com/yd8wp74
vs this
https://www.badcaps.net/forum/attach...achmentid=7336

and i wouldn't say it comes from same factory either, ergo, i said, sparkle is exempt.

[370forlife]

Re: Another Tagan, this time with failed Panasonic...

[QUOTE=i4004
oh yeah, i said what fortron models i inspected, didn't i?

now you tell us which models you inspected.
[/QUOTE]

http://www.newegg.com/Product/Produc...82E16817104951

http://www.newegg.com/Product/Produc...82E16817104045

those are just a few, but those both have 2 transistor 5vsb circuit. The 300W has OST, same for the 350W.

Well, back on ignore!

[i4004]

Re: Another Tagan, this time with failed Panasonic...

are you sure?
just a few days ago you were asking what exactly +5vstby circuit with a chip is:
https://www.badcaps.net/forum/showpo...51&postcount=1
and a while back you were not certian about 2 tr. design when you saw one
https://www.badcaps.net/forum/showpo...5&postcount=15
<wink>

something should be clear, as everell already wrote about it:
https://www.badcaps.net/forum/showth...itch#post90162

if you THINK you see transistor there, it doesn't automatically mean it is.
could be topswitch.

but yeah, in the end if it's 2 transistor design, it should be skipped.
models we get here (i can vouch for 350 and 400PNF and also some blue storm models) have decent 5vstby fortrons.
aynthing with 2 tr. design should be skipped, regardless of manufacturer.

>Well, back on ignore!