Annoying heavy load-failure in Tecnoware Free Silent 500W

[mockingbird]

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

Be careful with those ASUS items.

I have experience with the board he's using - the P5B - as I use it myself...

omega - you should certainly replace the at least the VRM high capacitors which are most certainly KZG on this particular board, as well as the Toshin Kyogo capacitors scattered throughout the board.

It's a very capable motherboard, even today.

[momaka]

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

In choosing Nichicon caps on RS, I discovered that there no apparent indication of ESR value. On the other hand, lifetime at 105 °C is indicated. I do hope 1000-2000 hours is not too little.

Do you know what series they were? Nichicon usually uses a 2-letter name, like for example VR, VZ, HM, HN, etc.

If RS does list the series, look for these:
Manufacturer.................Series
Nichicon ................................ PW, PM, PS, PJ, PV, HE, HD, HW
United Chemicon (UCC) ............ KY, KYA, KYB, KZE, LXV, LXY, LXZ, KZH, KZM
Panasonic .............................. FC, FK, HFQ (old stock only), FR, FM
Samxon ................................. RS
Rubycon ................................ YXJ, YXG, ZL, ZLJ, ZLK

That's not feasible, because old diodes are much bigger and different pitch

It is possible, - you can bend the leads... BUT, there's not much point in upgrading the 3.3 V and 5 V rail rectifiers. Just the 12 V rail, which I think even the FAL500DF2 PSUs probably use a 16 A fast-recovery rectifier.

I attached the pics you requested, including that of the fan and the specifications in the case of the PSU for your reference. In the first pic you can also see the black wires of sort of sensor which lies inside the right coil.

Ah, okay. So the fan has a thermal "controller" (well, sort of - this is just a really cheap and "dirty" way to it). The "sensor" in the coil is probably a NTC thermistor - as the surface of the coil gets hot, it heats the NTC thermistor as well. As the NTC thermistor heats up, its resistance drops and makes the fan spin faster.
^ That's in theory, though. In reality, as the fan draws current through the thermistor, the thermistor heats up, which makes it let more current through which makes it heat even faster until the fan is spinning near full speed. So it probably isn't doing to much to regulate the fan speed, but I think we can leave it alone for the time being.

In facts, between the two coils (see pic) there are two uncommon 1W resistors, that's 110 [?] and 51 [?] ohm, respectively (the latter is invisible in the pic).

Yup, that's two of the load resistors.

The 51 Ohm resistor (color code: green, brown, black, gold) appears to be for the 5 V rail. That means, it is dissipating around 0.5 Watts, which is not too bad.

The 110 Ohm resistor (color code: brown, brown, brown, gold?) appears to be connected between -12 V rail and 5 V rail. But can you verify this? If this is true, then it will be dissipating close to 2.6 Watts, which is way too much. I will wait for you to confirm, but if true, I suggest you remove that resistor.

There also appears to a unpopulated fan header spot on the PCB between small coil and 5 VSB purple wire. Was there anything in that spot at all originally?

Yes I get a box full. But as you saw, unfortunately I have cut all wires and disposed all the cases and restoring them now maybe would be not worth of.

Well, keep them for now. Maybe even open a new thread for those PSUs and try to see what the problem is?

If in the future you get more crappy PSUs (but with 80 mm fans), you can put these old PSUs in their cases and solder the wires from the crappy PSUs on these PSUs. Then you are back in business

[omega]

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

Dear Momaka,
thanks for your very informative reply!

If RS does list the series, look for these:
Manufacturer.................Series
Nichicon ................................ PW, PM, PS, PJ, PV, HE, HD, HW
United Chemicon (UCC) ............ KY, KYA, KYB, KZE, LXV, LXY, LXZ, KZH, KZM
Panasonic .............................. FC, FK, HFQ (old stock only), FR, FM
Samxon ................................. RS
Rubycon ................................ YXJ, YXG, ZL, ZLJ, ZLK

I edited my order draft to RS, by replacing caps which did not fit those series. I guess that the low impedance/ESR (are they synonymous?) which is not reported, has somewhat to do with ripple current (reported): the more, the better!

Just the 12 V rail, which I think even the FAL500DF2 PSUs probably use a 16 A fast-recovery rectifier.

You are wrong here: it is a SF2004PT 20 A fast-recovery (not Schottky however). Anyway, the right Schottky (I chose MBR40L60CTG) only costs 1 € each, it is not worth of replacing with a used one.

The 110 Ohm resistor (color code: brown, brown, brown, gold?) appears to be connected between -12 V rail and 5 V rail. But can you verify this? If this is true, then it will be dissipating close to 2.6 Watts, which is way too much. I will wait for you to confirm, but if true, I suggest you remove that resistor.

You are right. That resistor connects -12 to +5 rails. I will remove it, but I do hope the PSU so heavy modified will not eventually explode because of its possible critic points

There also appears to a unpopulated fan header spot on the PCB between small coil and 5 VSB purple wire. Was there anything in that spot at all originally?

No, I haven't touched the originally designed PSU, so far.

What do you suggest me to fix possible component vibrations? Hot glue or whatever?

A happy New Year to you and the forum!

[momaka]

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

I guess that the low impedance/ESR (are they synonymous?)

More or less, yes.
If I remember correctly, ESR and impedance are equal usually at 100 KHz frequency, or something like that. Beyond that, they are very similar, but not quite the same.

You are wrong here: it is a SF2004PT 20 A fast-recovery (not Schottky however).

Ah yes, you did mention that in post #15. I just forgot

You are right. That resistor connects -12 to +5 rails. I will remove it, but I do hope the PSU so heavy modified will not eventually explode because of its possible critic points

It should be okay. That load resistor is there to provide some load on the -12V rail so that it doesn't go too high. But most of the time, it won't - even with the other PSU rails loaded. I guess just measure the voltage once you are done fixing the PSU. If it goes above -13.2V, then you might need a load resistor - in that case, something like 510-680 Ohms might be more reasonable. 1-2 Watt resistor will do. But if the -12V rail stays within -10.8 to -13.2 Volts, then no need for a resistor.

No, I haven't touched the originally designed PSU, so far.

What do you suggest me to fix possible component vibrations? Hot glue or whatever?

No, that's not necessary.

I was just wondering why there is an empty spot for a fan header. But I think I figured it out, now. Probably the manufacturer had originally designed the PSU to have an external fan controller and get power from -12V and 5V rails.

A happy New Year to you and the forum!

Thanks!
Happy new year to you and the people around you as well

[Behemot]

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

I edited my order draft to RS, by replacing caps which did not fit those series. I guess that the low impedance/ESR (are they synonymous?) which is not reported, has somewhat to do with ripple current (reported): the more, the better!

I bet no matter what editing you do, it'll still be at least 2 times as expensive as my stock, incl. shipping…

[momaka]

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

I bet no matter what editing you do, it'll still be at least 2 times as expensive as my stock, incl. shipping…

Yeah, it's possible. But I think he's doing it because of the MBR40L60CTG rectifiers.

[Behemot]

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

Could still buy those in there and caps from me

[omega]

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

I have noticed that in that PSU the diodes (as well as the choppers) have been in contact to the heatsink through sort of pink gummy layer, without using any thermal paste. In the replacement of the diode, should I put some white paste between the back side of the diode and the gummy film?

[Behemot]

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

Won't hurt. The pads should be firm though, not any pasty stuff, in such case they are bad as they won't properly insulate.

[omega]

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

Won't hurt. The pads should be firm though, not any pasty stuff, in such case they are bad as they won't properly insulate.

Thanks Behemont, if I am not wrong there has to be a thermal but NOT an electric contact between the semiconductors and the heat sink, right?

[Behemot]

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

Yep - if they are TO-220 (with plain metal tab). TO-220FP is to be attached directly, as it is fully insulated, with some thermal compound applied.

[momaka]

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

I have noticed that in that PSU the diodes (as well as the choppers) have been in contact to the heatsink through sort of pink gummy layer, without using any thermal paste.

Is that for the Tecnoware FAL500DF2 or the FAL501FS12?
Because the FAL501FS12 (the one you first posted about in this thread) appears to be using the gray silicone pads. I don't see pink gummy stuff anywhere. At least not in this picture you posted:
https://www.badcaps.net/forum/attach...1&d=1451235758

As long as those silicone pads are intact (i.e. no rips or holes in them, other than the one to mount the diodes and transistors), then you can re-use them. No need to apply thermal compound.

In the replacement of the diode, should I put some white paste between the back side of the diode and the gummy film?

See above.

[omega]

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

Behemot and Momaka, Thanks so much for your answers!

Is that for the Tecnoware FAL500DF2 or the FAL501FS12?
Because the FAL501FS12 (the one you first posted about in this thread) appears to be using the gray silicone pads. I don't see pink gummy stuff anywhere. See above.

Momaka, You are right, they are indeed silicone pads on FAL501FS12 (can one buy them as spares?). As a chemist and NOT electronics expert, I still have troubles with the specific terms, forgive me please. However, I can sketch you silicone chemical formulas

By the way, in Oct. 2013 I also ordered few Corsair VS450 spare PSUs, one of them I have been using instead of the Tecnoware one. So far (about 1 year use) I got no trouble with the respective PC, but I also read here a thread where there were problems with defective C(r)apXon on them. Programmed obsolescence? Actually I did not understand whether the deprecated fact had been fixed in newer PSUs. Anyway, any suggestions?

[Behemot]

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

VS is nothing extra but still much better than these two wonders I'd guess…

[momaka]

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

Momaka, You are right, they are indeed silicone pads on FAL501FS12 (can one buy them as spares?).

Yes, I think most big online electronics stores do have them. But I don't know if they will come pre-cut or send you a big sheet to cut yourself.

That said, I never bought any myself. I usually re-use them from junk PSUs and TV boards.

As a chemist and NOT electronics expert, I still have troubles with the specific terms, forgive me please.

We understood each other, so no problems.

After all, science, technology, and math are all closely related. Of course, the pictures in this thread did help quite a bit too.

However, I can sketch you silicone chemical formulas

Haha . Nice!
I have a cousin who has a degree in chemistry (fuels and petrol, specifically). Hard stuff!

By the way, in Oct. 2013 I also ordered few Corsair VS450 spare PSUs, one of them I have been using instead of the Tecnoware one. So far (about 1 year use) I got no trouble with the respective PC, but I also read here a thread where there were problems with defective C(r)apXon on them. Programmed obsolescence? Actually I did not understand whether the deprecated fact had been fixed in newer PSUs. Anyway, any suggestions?

Probably best to order some spare caps. If your units have CapXon indeed, they will need a recap sooner rather than later. Yes, "programmed obsolescence" is a fine way to put it.

Other than that, as Behemot said, the VS series are decent PSUs. Should last a long time with a proper recap.

[omega]

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

If your units have CapXon indeed, they will need a recap sooner rather than later.

Ok I am curious, I will open and inspect the PSU soon.
I argue that if there is NO Capxon, PSU is fine and I will let it get old untouched in my machine
Otherwise have I to replace with SAME capacity, low ESR, high quality caps? (I ask you because you have suggested me to increase the capacities of recapping spares, I did not ask you the reason why). What about the rectifier in the 12V rail of that Corsair? Is it fine?

VS is nothing extra but still much better than these two wonders I'd guess…

I believe next time I will buy the replacing caps from you, Behemot!

Other than that, as Behemot said, the VS series are decent PSUs. Should last a long time with a proper recap.

Happy to read that!
Thanks again

[Behemot]

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

Big caps for filtering purposes replace with same or higher capacity, if possible. There are rare occasions when replacement is simply not available so than you have to do with what you got This has been e. g. FSP GLN series with custom crapxon 2200/6.3 D8 caps. No longer valid though…

[omega]

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

Hi, which kind of load would you suggest me to use in order to test the PSUs with a DSO before and after redioding/recapping? I would have thought to low voltage lamps, such as car lamps. But to build a standardized schematics (if any) developed by the forum for this purpose would be nice.

[Behemot]

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

Yeah car halogens are good, I myself use GY6.35 halogens. But you always have to use some kind of soft starting, I use 5A, aprox. 10R thermistors in series with each bulb. Bulbs have very high initial current.

[momaka]

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

I argue that if there is NO Capxon, PSU is fine and I will let it get old untouched in my machine
Otherwise have I to replace with SAME capacity, low ESR, high quality caps?

Yes.

(I ask you because you have suggested me to increase the capacities of recapping spares, I did not ask you the reason why).

The reason why is because those capacitances I suggested in post #16 are usually what a good quality power supply would use. Your FAL501FS12 had those 1500 uF caps everywhere simply because the manufacturer probably saved a few coins by not buying bigger 2200 uF caps. Same reason why there are no inductor coils between the caps - less parts to put in, less cost for the manufacturer.

Pinch a coin here and there and you can save a decent amount at the end of the day.

What about the rectifier in the 12V rail of that Corsair? Is it fine?

According to this review:
http://www.hardwareinsights.com/wp/c...s450-review/3/
... yes. You get two PFR30L60CT rectifiers in parallel on the 12V rail, which is more than enough. Of course, that is if this is what your PSU has too. If you open it, check and see for yourself.

Hi, which kind of load would you suggest me to use in order to test the PSUs with a DSO before and after redioding/recapping? I would have thought to low voltage lamps, such as car lamps.

Yes, 12 V halogen or incandescent lamps will do. I think even some Christmas incandescent light bulbs will work: either bulbs directly attached to the 5V rail or two bulbs in series connected to the 12V rail.