Be Quiet BQT P9-550W Dark Power PRO: Power Supply Fails to Start, Only Runs for 1-2 Seconds

Hello, I am the owner of Be Quiet power supply model BQT P9-550W Dark Power PRO, unfortunately already damaged. The UPS does not start up one day and it still keeps its state. I stripped the power supply, and initially there are no visible defects in any of the components.

symptoms:
The power supply after connecting to the load source and switching on (shorting the wires), starts literally for 1-2 seconds (turns the fan on for a few seconds and does not get up). When the power supply is turned on, you can hear a sound like a switch (it is not a sound of sizzle, sparks, etc.), but just such a strange changeover and then the power supply turns off (it takes 1-2 seconds). It is as if the power supply had the desire to run, but something stopped him access to the efficient world of power supplies .

The voltages on the green and purple wires are present and amount to + 5V.

Can anyone meet such a fault and how you can eliminate this fault, thank you for your tips and advice in advance.


I corrected TONI_2003.

Any other measurements you did? Check the relay.

Relay? Perhaps a strange question, but has this element some other electronic name? Mosfets and diodes look and check too are ok

I greet my colleagues.

Relays often use contact areas in relays.

Thank you very much for your answer. Honestly, I have looked at this element several times whether this snap / switch does not come from it. Unfortunately, today I have already finished the tin (how bad luck is bad luck ), I will go tomorrow, so I will come back to Volumen and pass the conclusions. Have a nice evening.
Edit: 29 Apr 2012 13:48
Hello again, and tin purchased ...
The measurements that I carried out on the main electrolytic capacitor are 320 volts at rest and, after starting, they rapidly increase to 400V, and then slowly drop to 320V.
resistance:
Black, and red - 91.8?
Black and yellow - 34,7?
Black and orange - 79.9?
Black, and blue - 0? (here it is so high that nothing appears on the meter, or it does not exist at all)
Black, and gray - 30?
So what else could I check?
corrected TONI_2003.

Hello,
Power supplies from this manufacturer (Be-Quiet) from the Dark Power series to run dry (without a board + other circuits) require a load (eg a bulb) + 5VSB pin.
They do not have their own intrins like others. artificial load.
Load one of the + 12V lines with a light bulb (so that you can see if it works), and a + 5VSB line (purple).
In these power supplies, voltage maintenance for fans is used, eg in the P7-Pro-450W model it is enough for 4 minutes, so the fan operation during this time can be illusive and does not actually mean the state of work.
Of course, the basic way to activate is to short-circuit PS_ON / OFF (green).
Voltage + 5VSB occurs only in the initial startup phase and is needed to initiate control of the CM6800 integrated circuit that activates the main converter.

Hello, the power supply is the same, whether I charge it or not. I have connected to two computers and the same symptom, something is heard that switches in it and turns off after a second. As a burden, probably 2 different computers are enough, they are not 486 so please do not tell me that I do not load the voltage lines, but I can also carry out the test with a light bulb, but in this case it is probably unnecessary.

I have read this topic, which my colleague presented as well as all on Elektród and I read it from cover to cover, however I did not find the same symptom and how to get rid of it. There are several topics with the same damage, but it applies to other brands of power supplies, although it is not important anyway because the construction of all is similar, however, these topics are not solved, so if someone will help me and certainly those people who are struggling with other power supplies they will benefit from it and their power supplies will be fixed.

I greet my colleagues

ampermen wrote:

connected to two computers and the same symptom, something is heard that switches in it and turns off after a second.

So you did not check this relay.
Easy way: desolder it from the plate and disassemble the top plastic cover.
You can connect the voltage on which you work, you will see if it switches well.

Thank you for the tip, but it seems to me that it is all in plastic (flooded with plastics all without places where you can see the connections) I desoldered it but I soldered again, but maybe if I split it, it will turn out to be "bingo". Although I am afraid that it is permanently flooded, and only breaking it down will give you the opportunity to see the middle.
Tomorrow we will see what will bring a new day. Because today is too late and I have poor eyesight for work in the dark.

PS.
If so, if it was really flooded, and I somehow split it, is it possible to damage it? I'm asking because I do not think I get something like that, I would probably have to throw the power supply back into the trash.

In any case, thank you for the tip.

Good night.