Corsair RM1000e - Help identify 5VSB Zener diode

[CapLeaker]

Don't need to be sarcastic. Just tell me that I'm wrong, I can accept. I'm an adult, not a 5 year old kid.

Not sarcastic at all. Just didn't make any sense! All you needed to do is to look for a detailed review of this PSU.

Here (page 3 is where the goodies are): https://hwbusters.com/psus/corsair-r...-psu-review/3/

Pull the data sheet of the Supervisor IC: https://www.techpowerup.com/articles...ges/WT7527.pdf

Read it, and it gives you all kinds of information on how it works and how to disable it. Now all major chips are listed in that review and thus you can pull up all the data sheets too! Carry on! 😉

[прямо]

Would be the slowest acting “protection mode” in the world. I haven't seen any protection mode that is that slow. I wonder what kind of voltages the op gets on the main filter cap?
I think the supervisor is a WT7527rt. It shuts the PSU down less than a half of a second.

Don't need to be sarcastic. Just tell me that I'm wrong, I can accept. I'm an adult, not a 5 year old kid.

[CapLeaker]

That's the protection mode kicking in, because 10.8V for 12V rails is an under voltage condition.

Would be the slowest acting “protection mode” in the world. I haven't seen any protection mode that is that slow. I wonder what kind of voltages the op gets on the main filter cap?
I think the supervisor is a WT7527rt. It shuts the PSU down less than a half of a second.

[Per Hansson]

It might not work without a load: connect something you don't care about, some old hard drives for example or a couple 12v car light bulbs to 12v and 5v outputs.

[прямо]

Nvm, I have 12v1 and 12v2, tester connector was a little loose. However, they're only 10.8V. And after 10-15 seconds I can hear a relay click and the supply shuts down.

That's the protection mode kicking in, because 10.8V for 12V rails is an under voltage condition.

[hobostove]

Adding some photos here

[hobostove]

Nvm, I have 12v1 and 12v2, tester connector was a little loose. However, they're only 10.8V. And after 10-15 seconds I can hear a relay click and the supply shuts down.

[hobostove]

I found a shorted transistor on the hot side with a thermal cam. Replaced it and 5VSB started up. Now I can see that I'm missing 12v1, and 12v2 is at 11V. 3.3V is fine. Time for more troubleshooting!

[прямо]

Also worth to check the 5VSB feed back as well just to make sure nothing is wrong with it. Next to its output caps there should be a TL431 and a voltage divider resistor network that set its 2.5V reference voltage, which then get feed back to the TNY chip through an optocoupler.

If one of that voltage divider resistor network fails (very rarely happens), or if the TL431 itself fails, or the optocoupler fails (happens quite often), then the TNY chip will not be able to regulate 5VSB to the correct 5V voltage.

[прямо]

5VSB is behaving strangely. It's fluctuating between 3-3.5V. It's a couple seconds from peak to peak

Replace the 5VSB output caps.

[hobostove]

5VSB is behaving strangely. It's fluctuating between 3-3.5V. It's a couple seconds from peak to peak

[прямо]

Just found main cap voltage is only 167V when powered up. Shouldn't it be 300V+? I'm on 120AC here, so maybe ~170V is normal?

That is normal. 120V AC / 0.707 = 169V DC.

It will be boosted by the PFC controller chip when the PSU is starting such as when you jumper PS_ON to ground.

If the boosting doesn't happen, check the supply voltage of the PFC controller chip. I don't know what chip it is, but the usual voltage is around 15V DC. Also, when you check this voltage, because the PFC controller chip is located at the primary side, the black lead of your multimeter should be at the negative pin of the bridge rectifier.

Be very careful though when poking around the high voltage side.

If the PFC controller chip supply voltage is present and around 15V DC, then the next logical step is to check the supervisor chip fault protection (FPO) pin. Consult the chip datasheet to see if it's an active high or an active low logic signal. If the FPO status is telling you that PSU is in protect mode, this explains why no pimary voltage boosting is happening and why the PSU won't start. Therefore, you have to disable the protection in order to force the PSU to start and proceed with diagnosing what is triggering the protection, usually it is because of an under voltage or an over voltage on one or some of the output rails.

But more importantly, is the 5VSB present?

[hobostove]

Just found main cap voltage is only 167V when powered up. Shouldn't it be 300V+? I'm on 120AC here, so maybe ~170V is normal?

[hobostove]

Parts came in today, and I replaced the 2.2o resistor, the zener, the flyback IC, and the optocoupler. Still no life so I suspect something is open up stream. Going to poke around a bit more

[Per Hansson]

Measure the optocoupler in diode test mode with your multimeter: since the failed ZD5 zener is parallell to it (talking about the example schematic that c1q3 posted here).

[hobostove]

It looks like the resistor is a 2.2ohm fusible. I couldn't find the exact one, but this is close: https://www.digikey.com/en/products/...52-2R2/2167125

That resistor is connected between 380V and Drain, so yup, it looks like it went pop as intended.

Source is connected to GND, and ZD5 connections match, so I think you found it! This looks like an OK replacement: https://www.digikey.com/en/products/...C15-7-F/755469

I can't find any shorts, so I'm going to order the diode, the resistor and a new TNY284 and hope for the best. Will report back in a week or so.

Thank you both!

[hobostove]

Incredible work c1q3, thank you very much. Thanks to you too Per Hansson. I will gather more info and confirm the drawings above when I'm in front of it tomorrow morning

[Per Hansson]

I could be wrong of course, these "special" resistor bands take a bit of guessing: the best way is to have more of the schematic available.
Right now I can't see where it connects to so I have no way to make a better educated guess.
But if it is before or after the source or drain for example then it is acting as a protection if the MOSFET in the TNY284 gets stuck on...
(And if you look at the top-side photo above it seems the PCB around the drain leg is discolored so I'd say this is what has happened).
And welcome to Badcaps btw and good job so far with the circuit

[c1q3]

I think the resistor is a 2.2Ω fusible resistor, it looks like it did it's job and is no longer a resistor

https://www.engr.siu.edu/staff/spezi...standscode.pdf

so the third golden ring is like blank space in numeral. Interesting.

[Per Hansson]

I think the resistor is a 2.2Ω fusible resistor, it looks like it did it's job and is no longer a resistor

https://www.engr.siu.edu/staff/spezi...standscode.pdf