Aerocool Strike-X 1100W shutting down

[Arandy]

Hello,

I am trying to diagnose and fix an issue with the ATX power supply in the subject. Aerocool Strike-X 1100W.

One day, it simply did not power on. It's behaviour is bizzarre. When powered on after being poweredoff for a while, it starts for a few seconds, cooling fan spins and then shuts down. Using power button on PC case didn't sort any effets at all.

So I replaced it with anoter PSU and put it on my workbench. I Opened it and did some visual inspection....nothing suspicios was in place, no overheating, no smells. All capacitors were fine...I just broke one by accident (on the secondary), and replaced with a spare I had.

I attached a power supply voltage analizer and tried to check voltages...but the psu does not stays power-on enough to see the values.

I did a few checks and I think the "primary" side is OK, I measured 360V on capacitors, constant.

So I thought that there is something BAD on the "secondary" part of this PSU that is detected by the ps232s which then immediatelly turns off the unit.

I've found the 2 photo-diodes driven by it and connected to the "primary".

So I tried to shortcut them manually, and I've fount that just one of them, when the pins on the secondary side are short, it makes the PSU ALIVE!!!!

BUT, functioning like this I hear some weird noises...(coil whine?) and I can finally see some values on the psu tester I connected.

For security and pratical reasons I soldered a microswitch to those 2 pins. So I can FORCE ON the PSU easily when I want so I can read the voltages.

I've attached below some PICs of the pcb and 2 videos showing the behaviour descrbed above.

I see now that the 3.3v and 5v rails are rock stable but +12V line is very unstable...it fluctuates from 10v to 13.8v quite often! -12V line looks like inflienced by it too...and PS is 0 (shouldn't be a value between 50 and 200ms?)!!

What's happening inside this PSU? Bad Mosfets? Bad Caps?

Thank you!











Video 1 - poweron then immediate shutdown

Video 2 - Psu in state of "forced ON"

[sam_sam_sam]

Re: Aerocool Strike-X 1100W shutting down

Your 12 volt rail has some issues because it is high voltage 13.something try but a MR16 50 watt incandescent light bulb on this rail and see if the voltage comes down a little bit the other 12 volt rail also has some issues as well it’s voltage is not stable either

Also the capacitors are a non brand name which I would highly recommend you put some name brand capacitors in this switching power supply ( do you have a ESR capacitor tester I would test all capacitors that are less than 100uf )

The surface mount capacitor that you replace was it because they were shorted

In your 4 picture of the capacitors on the board are a non brand name type of capacitors I would highly recommend replacing them as well

[Arandy]

Re: Aerocool Strike-X 1100W shutting down

Also the capacitors are a non brand name which I would highly recommend you put some name brand capacitors in this switching power supply ( do you have a ESR capacitor tester I would test all capacitors that are less than 100uf )

In your 4 picture of the capacitors on the board are a non brand name type of capacitors I would highly recommend replacing them as well

Hello there :-)

Uhm...can you point me to some proper brand? It is very difficult to find 3300uf 16V capacitor 25mm lenght and 10mm diameter. Where can I find them? Mouser.com?

Thank you!