FSP400-60GLN worth fixing?

[goodpsusearch]

Re: FSP400-60GLN worth fixing?

lol

[momaka]

Re: FSP400-60GLN worth fixing?

I kinda wonder what do you mean about availability when I have pretty much everything regarding ATX PSUs for like 8 years straight now and you can just go and buy the caps from me here in Prague, like RIGHT NOW.

Maybe you need to advertise more within your locale.
An infomercial about bad caps would be nice for a change!

Something along the lines of:
Are you struggling to find good caps online?
Tired of doing the same repairs over and over?
Do you feel your life is shorter because you can't find good quality products anymore?
...
Stop buying bad caps and get good quality Japanese caps from us for only $19.95
...
Limited time offer! Hurry and call now to get your good Japanese caps today!
And if you call in the next 5 minutes, we will double your offer. Just pay separate shipping and handling
.
.
.
Oops, I think I left nothing good for the imagination after this. :\

[zxcygnus]

Re: FSP400-60GLN worth fixing?

Shitano is known crap which tends to bloat in storage. I kinda wonder what do you mean about availability when I have pretty much everything regarding ATX PSUs for like 8 years straight now and you can just go and buy the caps from me here in Prague, like RIGHT NOW.

Maybe i will buy from you next time. This time i just bought material in store which i have almost across street from my office (plus I already have my own stock for another purposes).

But i can confirm, some capacitors really are able bloat in storage even never used. I don't remember which ones exactly it was. But they was not Hitano ESX.

Time will tell and maybe i will write it here :-)

[Behemot]

Re: FSP400-60GLN worth fixing?

Shitano is known crap which tends to bloat in storage. I kinda wonder what do you mean about availability when I have pretty much everything regarding ATX PSUs for like 8 years straight now and you can just go and buy the caps from me here in Prague, like RIGHT NOW.

[momaka]

Re: FSP400-60GLN worth fixing?

[QUOTE=zxcygnus;963858]So i just replaced all remaining capacitors and guess what? It works just fine. It's kinda boring.[/quotes]
Sounds about right, though.
With the bad caps, the PSU/3.3V rail probably wasn't regulating well, and that's why those diodes ran hot.

Voltage is still little lower (3.28 - 3.29V), but does't drop more. Mainboard itself reports even lower value, but i rather beleive to multimeter, this small one doesn't look much, but i verified it recently and it works fine.

Always trust your multimeter and never the motherboard voltage sensors (unless your multimeter has low batteries - only then you will likely see higher voltage than what they actually are.) To date, I have not found a motherboard that has accurate voltage sensors. They always seem to mess up on at least one rail (but often more.)

[zxcygnus]

Re: FSP400-60GLN worth fixing?

So i just replaced all remaining capacitors and guess what? It works just fine. It's kinda boring.

I found one C32 which i forgotten replace in 2016, so i replaced even smallest ones (2.2μF). Now it runs on my desk almost one hour continuously and nothing bad happened yet. No explosion, no overheating, all voltages are how it should be.

My retro PC probably never will exceed 100W of total consumption, so 400W PSU should be adequate. And cold PSU will probably last much longer, i hope.

For fun i tried write email to Fortron, but they told me "schematics are confidential, so we are not sharing them". I expected it.

As replacement capacitors i used mostly Hitano ESX and some Panasonics. Hitano are not best, but not worst either, and are easilly available for me locally. Where i could i used capacitors for little higher voltage (unfortunatelly little bigger too). I even opened one Capxon (2200μF/6.3V) and one Hitano (2200μF/10V) for comparison. Hitano looks inside little better, electrodes are significantly thicker, but that is all i can say. Time will tell.

Problem with diodes was probably because PSU was not able hold 3.3V properly as it should and load from mainboard was enough to drop voltage under 3V (what i measured), now it is ok. Voltage is still little lower (3.28 - 3.29V), but does't drop more. Mainboard itself reports even lower value, but i rather beleive to multimeter, this small one doesn't look much, but i verified it recently and it works fine.

[Per Hansson]

Re: FSP400-60GLN worth fixing?

I do not have those diode spots populated in mine.
And neither does everell if you look back in this thread at the pictures of his unit.
The only purpose I can think of is since this is a group regulated unit:
That it is some protection to not allow the 5v & 3.3v to get too far apart?
Is your retro PC maybe putting an uneven load on the PSU?

[zxcygnus]

Re: FSP400-60GLN worth fixing?

Hello, i am new here and i found this thread, because i have too this power supply with some weird behavior.

It works without any load, all voltages seems to be in tollerance. Many years ago (2016?) i replaced almost all capacitors, shortly tested it and just put it in my storage. Now PSU can be handy for my retro PC, but with mainboard Asus K8N-E two diodes D36 & D37 (2x HER108) connected in series between 5V and 3.3V outputs going very hot. And i don't know why. I even did not found these diodes on any schema which i was able found.

There is nothing burned yet, no bad solder joints as far as i can tell, no bulging capacitors (mostly replaced, and tested). I didn't tested last two capacitors C41 and one smallest just in neighborhood od C45 and L30. I will do it, as soon as i will gather some more components from my workshop.

Do you have any idea why these diodes D36, D37 are there?

Now, i just carefully poking around with multimeter and trying better understand which is connected where and why, because i have some education and experience with electronics, but these ATX power supplies are still new to me.

I know, i know, ATX PSU are cheap and i can easilly buy new one. But i want learn some more about it and this one seems to be in pretty good shape, so i hope it is just some banality.

[Behemot]

Re: FSP400-60GLN worth fixing?

It still behaves strange. Some boards work fine, some not. Not sure what exactly is that connected with as the unit already works OK on artificial load or with only hard-drive connected (before the hard drive would try, but was not able to start the motor).

I'll just keep it for testing, it's been replaced with Corsair VS550.

[momaka]

Re: FSP400-60GLN worth fixing?

^ Interesting fault.
Perhaps the low load on the 5VSB is making the primary side auxiliary rail (and sec. aux. rail, if there is one) low, thus somehow affecting the operation of either the supervisor IC or the PWM/APFC controller(s).

In that case, maybe use 2x 100 Ohm resistors in parallel as minimum load on the 5VSB, just to be on the safe side. Or increase the capacity of the filter capacitors for the standby auxiliary rails (though I am not sure that will alleviate the issue.)

[Behemot]

Re: FSP400-60GLN worth fixing?

No idea why this is happening or what did I broke during the usual fix, but the latest BS II 500 W outputs low +12 V (and no PG signal) unless the stand-by rail gets loaded by at least 100ohm resistor (0,05 A). So I guess I'll just put some SMD (or two 220ohm) ones somethere on the rail as minimum load resistor

BTW, this time there was fast enough diode, but the zener on the output of the tap feeding driving circuitry was kinda overheating from the ripple (that cap was half-way dead as well as the 22uF one directly on the SB driver input).

[Behemot]

Re: FSP400-60GLN worth fixing?

Ask your students how many caps under 5000 uF and 200 V they reformed in them industries than. Cause doing that is like injecting oneself with a plague. Economical suicide. It's better to throw old caps away and buy new ones that test or reform them.

From what I see, only thing which was confirmed is that KZG's go bad, which we already knew. Other than that, I've seen that ocassionally mentioned in other threads, few Samxons, maybe some Sanyos, but all that cases reach fraction of caps which go through my hands. Even with 10 yo new-old stock caps, I've never encountered single bad like that.

Wonder what's Topcats experience, I think it will be more like mine. I am not saying it can not happen, but the number of such cases is NOT a reasonable base for making any conclusion. Not when there are thousands of caps with NOT a single failed one.

[Elitist]

Re: FSP400-60GLN worth fixing?

Thanks guys for confirming what I reported. I do NOT provide fake data! Bh seems to think he knows more than my students who worked within the industry. Shame as he's provided a lot of insight and assistance from the practical side of PSUs.

[Wester547]

Re: FSP400-60GLN worth fixing?

It is true that the ultra low ESR electrolytic caps are more unstable and some may develop problems after a good few years in storage...

The worst storage bulger by far is KZG (as far as Japanese ultra low ESR caps go), especially the 6.3V variants. KZJ comes close though (the 10mm diameter 6.3V variants), as might Sanyo/Suncon WF (doesn’t matter which variants). IMO, Rubycon MBZ/MHZ and Panasonic FJ/FJS/FL are generally the most reliable of all the ultra low ESR caps. Rubycon MCZ/MFZ aren’t terrible but they seem somewhat quick to vent from excessive heat. Sanyo/Suncon WG I have mixed experiences with, but the newer ones seem to fare better.

but overall, I too have rarely seen failure. Like Behemot, I have a stock of about 200 or so total Rubycon MFZ and MCZ as well as Nichicon HN and HZ (all pulled from Xbox 360 consoles - i.e. used caps). I just opened my glass jars of them the other day as I needed a few, and noted that I had 2x Nichicon HZ 6.3V/2200 uF that had bulged by themselves. Upon closer inspection, both of these turned out to have a date code of H05xx, which is known to have some problems (though not as bad as H01-H04 datecodes).

In my experience, late 2004 - early 2005 dated HM/HN/HZ aren’t as bad as those made in mid 2001 - early-mid 2004, but I’ve seen enough of them fail to avoid them altogether.

Thus, I re-tested all my H05 HZ stock and found 2 more caps with border-line in spec high capacity (2700 uF) and one out of spec (3800 uF). This indicates some of these H05 HZs have started to break down. What's interesting is that I reformed and checked all of them roughly 2 years ago, and none had a problem. Some of them, I stored with full plate charge, while others I stored discharged in order to see if that would make a difference. But it didn't - one of the failed HZs was stored with a charge and the other was not. Same for the HZs that read high capacity.

Don’t tell me... the one that measures 2700uF was the one you stored with a charge.

In an electrolytic capacitor, the capacitance is inversely proportional to the thickness of the dielectric (although the surface area of the aluminum foil is also a factor). That means as the dielectric thins, capacitance increases, the breakdown voltage decreases, and vice versa.

Yes, you read that right, some of the 6.3V caps had negative charge on their plates from sitting in storage. This indeed indicates that lower-voltage higher capacity caps are indeed probably more prone to going bad in storage due to thinner oxide layer (or at least aging faster than their 10V and 16V counterparts).

Seems that way. In the now venerable Dell Optiplex GX240, GX260, and Dell Dimension 4300 machines, the 2200uF 6.3V Nichicon HM with bad datecodes have the highest failure rate on their motherboards, whilst the 1800uF 16V and 1000uF 16V Nichicon HM that filter the +12V VRM input, even with bad datecodes, are often fine even after many years of use. This might be because the 2200uF 6.3V caps are closest to the CPU heatsink, but I take it as more of an indication that the 6.3V caps simply age faster (although the +12V caps have to deal with much less ripple current).

But again, after a quick reform on some of these caps, I had no problem using them again.

The caps that had a negative charge on their plates were fine after you reformed them?

[momaka]

Re: FSP400-60GLN worth fixing?

It is true that the ultra low ESR electrolytic caps are more unstable and some may develop problems after a good few years in storage... but overall, I too have rarely seen failure. Like Behemot, I have a stock of about 200 or so total Rubycon MFZ and MCZ as well as Nichicon HN and HZ (all pulled from Xbox 360 consoles - i.e. used caps). I just opened my glass jars of them the other day as I needed a few, and noted that I had 2x Nichicon HZ 6.3V/2200 uF that had bulged by themselves. Upon closer inspection, both of these turned out to have a date code of H05xx, which is known to have some problems (though not as bad as H01-H04 datecodes). Thus, I re-tested all my H05 HZ stock and found 2 more caps with border-line in spec high capacity (2700 uF) and one out of spec (3800 uF). This indicates some of these H05 HZs have started to break down. What's interesting is that I reformed and checked all of them roughly 2 years ago, and none had a problem. Some of them, I stored with full plate charge, while others I stored discharged in order to see if that would make a difference. But it didn't - one of the failed HZs was stored with a charge and the other was not. Same for the HZs that read high capacity.

But other than those Nichicon HZ caps with H05 datecodes, all my other ultra-low ESR caps read in spec, including all H06 and later Nichicon HZ caps. Now, I did notice that from these caps, most of the 16V caps that I stored with a full plate charge (15.5V) still retained some of it (ranging from 5 to 14V). Meanwhile, none of the 6.3V caps that I stored with a full plate charge (of 6V) retained anything - most read between -0.5 to 0V. Yes, you read that right, some of the 6.3V caps had negative charge on their plates from sitting in storage.

This indeed indicates that lower-voltage higher capacity caps are indeed probably more prone to going bad in storage due to thinner oxide layer (or at least aging faster than their 10V and 16V counterparts). But again, after a quick reform on some of these caps, I had no problem using them again. And as I noted above, except for the problematic Nichicon HZ with H05 datecode, all other caps read in spec.

[Behemot]

Re: FSP400-60GLN worth fixing?

Sir, I do not know where you live, but tantalum is becoming dead (in mainstream electronics anyway) is it can not cope with MLCC in terms of capacity density, price and reliability. Plus ceramics usuall do not tend to catch on fire

As for recommended storage, no datasheet talks about anything like that. Either the caps were way too old (remember the ultra-low ESR caps are way more unstable and less reliable than other types, the have short lifetime even new), got frozen during transport (or similarly damaged) or they were fakes.

I do store about 1500 Rubycon MBZ and MFZ (with 500 already in use - aprox.) and none of them failed yet. Same with couple hundred Pannies or Samxons GC. So the statistics is clear - you are single exception, or there was problem with the caps even before you got them. Interesting how you jump to conclusions and creating wild theories after half a dozen bad caps.

[Elitist]

Re: FSP400-60GLN worth fixing?

they silently died

- yup, in storage. I believe the recommended storage protocol is to ramp up to rated every so often (but nobody does this except, perhaps, a few manufacturers with excess stock). A lower level continuous 'soak' also preserves the film without risking the organics in the electrolyte, aqueous solvent or not. Again, rarely done in practice. No wonder the trade is transferring to tantalum, but (i) not much option for mobiles (ii) tantalum is rare, very expensive/difficult to extract & refine (iii) Coltan mineral source in DRC and slave labour raises ethical concerns.

[Wester547]

Re: FSP400-60GLN worth fixing?

So you’re saying they didn’t bulge or leak but that they silently died? I don’t doubt that the oxide film deteriorates in storage and must be restored using the proper precautions (applying the rated voltage every 18-24 months at least).

[Elitist]

Re: FSP400-60GLN worth fixing?

Extremely unlikely as I usually replace one at a time into the same configuration. Bit puzzled why there's such doubt about storage deterioration? Makes perfect sense to me! They didn't blow, they failed fairly quietly if I remember and replacement with new stock fixed the problem.

[Wester547]

Re: FSP400-60GLN worth fixing?

Did you try to install them “backwards” on a motherboard whose polarity markings were backwards (the + sign on the shaded half of the polarity circle)? Of course something like that would be obvious, but sometimes even the best techs may make simple mistakes such as that. It could certainly explain why they suddenly blew.