Annoying heavy load-failure in Tecnoware Free Silent 500W

[momaka]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

I already wrote that at the beginning, this PSU has been working excellent, therefore something has been slightly failing in somewhat with time!

It may appear like it was "working excellent", but the truth is, such low quality PSUs *never* do. The problem is that you don't see anything wrong on the surface. But the lifetime of the HDD and other system components is greatly reduced, which is why you got those "ATAPI errors". And the more you use these PSUs, the more "errors" and "bugs" will appear. You will get to a point where you will be pulling your hair all the time, because of all of the problems these PSUs will cause eventually.

Anyway, the point is: I have few more such spare PSUs, but no money to buy others (research budget is so low in South Italy!).
So I have to choose ether to repair them or stopping researching and perish
So please forgive me when I insist to ask how to fix it

No need to be sorry here.

If you really have no other option but to fix these power supplies, we will help you, because any kind of fix or "upgrade" on these PSUs would be better than using them the way they are right now.

However, let me just warn you that the parts for these PSUs may cost almost as much as buying a used PSU.

At a minimum, you will need:
* four (4) 6.3V or 10V, 2200 uF capacitors
* two (2) 16V or 25V, 1500 uF capacitors
* two (1) 6.3V or 10V, 1000 uF capacitor
* one (1) 16V or 25V, 470 uF capacitor
* one (1) 20 Amp, 60-100V schottky rectifier (TO-220 or TO-247, 3-pin with common-cathode)
* two (2) 50V, 1-10 uF capacitors (will tell you specifically when I see more pictures of the PSU)
* one (1) 50V, 1-47 uF capacitor (will tell you specifically when I see more pictures of the PSU)

^ These are all of the parts for one (1) power supply. Also, if you want your repair to last, you should use only quality Japanese capacitors. That means avoiding eBay (especially sellers from China). And even then, the fixed power supply still won't be decent by a long shot. But those parts may be just enough to keep the PC alive and not crash.

Also, I would suggest adding more pictures here so we can see exactly what we are working with (preferably, one picture of each side of the PSU). And if you can, give us the part numbers you see on the parts mounted on the heatsinks (radiators). I actually have an idea of what they will be, but would just like for you to confirm. (Probably 13007 NPN BJTs for the main PS with 10-15 Amp schottkies for the 3.3V and 5V rails, and 10 Amp or *maybe* 12 Amp FR rectifier for the 12V rail. 5VSB probably standard 2-transistor motherboard killer design.)

I have to care 18 such machines :-(

Ouch!
Do they ALL use this same exact PSU?!

If that's the case, I think you might be better off finding a few used but *good quality* power supplies for cheap and fixing only a few of those machines than spending all of the money on parts to fix these cheaper power supplies. But I will wait for your response.

And no matter the load, you can bet on it being "raw power." You made a funny and didn't even realize it!

Hehe. Nope, wasn't trying to be funny at all here .
Whenever dealing with low-quality PSUs, I always try to refer to the output power as being RAW, precisely because of all of the ripple and noise.

...by crushing it under your feet!

Believe it or not, I've never done that. Even the cheapest and most low-quality PSUs still have at least a few parts worthwhile of taking.
I actually had a super-gutless wonder PSU that helped me save at least two other PSUs (one of them was a good quality HiPro, the other a 105W, 12V halogen light converter), a CRT monitor, and a few other things I can't remember without digging a bit in my "repair" gallery. Also was a good source of parts for my college projects. And best of all, it was an excellent lesson to further improve my desoldering skills (this was back when I joined BCN).

So yes, I have respect even for the worst PSUs.

[omega]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

You can easily find another psu for free that will be worth repairing. Recycling centers and PC shops are full of them. There are also for sale on ebay or else for ~5 euros.

I have to care 18 such machines :-(

[goodpsusearch]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

You can easily find another psu for free that will be worth repairing. Recycling centers and PC shops are full of them. There are also for sale on ebay or else for ~5 euros.

[omega]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

Thanks so much for all your answers! I already wrote that at the beginning, this PSU has been working excellent, therefore something has been slightly failing in somewhat with time!
Anyway, the point is: I have few more such spare PSUs, but no money to buy others (research budget is so low in South Italy!).
So I have to choose ether to repair them or stopping researching and perish
So please forgive me when I insist to ask how to fix it

[kaboom]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

Welcome, omega!


Unfortunately, there isn't much you can repair in this power supply. The PSU you have there is a "cheapo" one... in other words, very low quality. The output caps may appear good, but that's not the problem. The problem is they are too small to "clean" the power that comes out of this PSU. And even if you did install the proper size capacitors, the board layout in this PSU does not have space for output PI coils (inductors). That means the components in your PC will be fed with dirty power... i.e. unstable voltages with many spikes. This is precisely why you are getting HDD-related errors. If you leave this PSU in your system, I guarantee it will make your HDDs fail very soon.

If they haven't been damaged already...

Also, the "500W" rating is absolutely fake! At most, this power supply will give you 200 Watts raw power.

The solution I suggest to you is to NOT use this PSU.

The "500W" rating is made up, as usual. And no matter the load, you can bet on it being "raw power." You made a funny and didn't even realize it!

Even at 500mW out, you'll be getting more AC than DC.

You can try to fix it...

...by crushing it under your feet!

Been there, done that.

[goontron]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

Another one with momaka... Scrap it!

[goodpsusearch]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

I completely agree with momaka

[momaka]

Re: Annoying heavy load-failure in Tecnoware Free Silent 500W

Welcome, omega!

what do you advise me to check to find the culprit compontent(s) (if any) to repair? In other words, how to approach the troubleshooting of this annoying intermittent failure?

Unfortunately, there isn't much you can repair in this power supply. The PSU you have there is a "cheapo" one... in other words, very low quality. The output caps may appear good, but that's not the problem. The problem is they are too small to "clean" the power that comes out of this PSU. And even if you did install the proper size capacitors, the board layout in this PSU does not have space for output PI coils (inductors). That means the components in your PC will be fed with dirty power... i.e. unstable voltages with many spikes. This is precisely why you are getting HDD-related errors. If you leave this PSU in your system, I guarantee it will make your HDDs fail very soon.

Also, the "500W" rating is absolutely fake! At most, this power supply will give you 200 Watts raw power.

The solution I suggest to you is to NOT use this PSU.

You can try to fix it as a learning experience (and we will gladly help you with that). But please do NOT use it in a computer that is important to you (or anyone else), because these cheap low quality PSUs are well known to blow up and kill other PC components with them.

Here are some examples of what GOOD power supplies look like:
https://www.badcaps.net/forum/showthread.php?t=7335

[omega]

Hello all, this is my first post here, so please be clement.
The machine I am mantaining is a Intel Q6600 QuadCore/based and is equipped with a Tecnoware 500W SMPS Cod. FAL501FS12. It has been working on heavy load (four physical HDDs) 24h/365d. That PSU usually works good for few months, then my machine invariably begins to undergo some serious ATAPI errors to their HDDs, that's IMHO a sign of some failure in the +12 PSU line. However on my inspection, the PSU seems good, I have been checking all secondary caps and the are good both in shape and in ESR (as checked with Blue ESR Meter). The PSU is still indeed good for normal duties, but for intensive job has to be replaced. This happened few times in the last few years.
My question: according to your knowledge, what do you advise me to check to find the culprit compontent(s) (if any) to repair? In other words, how to approach the troubleshooting of this annoying intermittent failure?
I think your hints may be useful to other amateur PSU servicers.
Your attention and possible help is greatly appreciated.