Help with HSTNS-PD11 (pn:438202-002) DPS1200FB

[tirman]

 I'm trying to repair a PSU HSTNS-PD11 (pn:438202-002). This power has all outputs  4,8V and 12V STBY ok....  but ...there isn't 12V output! I pulled out a control board (+12VFB), but I couldn't find any failure. Do you know where is 12V ouput control? Could you help me? I've checked all mosfet and capacitor....

I'll upload some photos. I promise.

[tirman]

Pin 27= 4,8V
I connected a ATX64P6 board to turn on the PSU, then these are the values:

Pin 28=4,84V
Pin 29=4,84V
Pin 30=0,1mV
Pin 31=4,8V
Pin 32=4,8V
X Pin 33= 0,63V (and 2,9V when it's only plugged to AC and PSON no activated)
Pin 34=6mv
X Pin 36=0,63V
Pin 37 (STBY)=12V
Pin 38 = ---
X Pin 64 (12V)= 0V

The PSU turns on and shows 12V, but few seconds later it drops off.

I've atttached a pinout that I think it's similar to my PSU and some photos of the board "12VFB".

[eblc1388]

I connected a ATX64P6 board to turn on the PSU, then these are the values:

There is a very high probability that the ATX64P6 is not compatible with the PD11, unless it works with other PD11 before. You should manually test the PSU before removing the 12VFB board. Here are the steps:

1. connects a 18K ~ 22K resistor from Pin36 to Pin37(12V SB). This will make the PSU believe that it is inserted into a power slot of the server.

2. jumper Pin33 to GND to start the PSU. If main 12V output becomes available, then you can be sure that the ATX64P6 board is at fault.

The PSU turns on and shows 12V, but few seconds later it drops off.

If main output did produce 12V, then the protection of the power supply likely to be triggered and shutdown the supply. It would not be possible to easily know why this happens. These type of power supply has a ton of monitoring on various parameters(like undervoltage, overvoltage, overcurrent, ....) both via hardware comparator and ADC pins of MCU, making it virtually impossible to troubleshoot unless one has got the full schematic of the power supply.

[tirman]

Great eblc1388! Thanks for your help!

 I´ll try with your advice.

[tirman]

I connected a ATX64P6 board to turn on the PSU, then these are the values:

There is a very high probability that the ATX64P6 is not compatible with the PD11, unless it works with other PD11 before. You should manually test the PSU before removing the 12VFB board. Here are the steps:

1. connects a 18K ~ 22K resistor from Pin36 to Pin37(12V SB). This will make the PSU believe that it is inserted into a power slot of the server.

2. jumper Pin33 to GND to start the PSU. If main 12V output becomes available, then you can be sure that the ATX64P6 board is at fault.

The PSU turns on and shows 12V, but few seconds later it drops off.

If main output did produce 12V, then the protection of the power supply likely to be triggered and shutdown the supply. It would not be possible to easily know why this happens. These type of power supply has a ton of monitoring on various parameters(like undervoltage, overvoltage, overcurrent, ....) both via hardware comparator and ADC pins of MCU, making it virtually impossible to troubleshoot unless one has got the full schematic of the power supply.

I followed your steps.  The output 12V is... in fact... 0V, but the cooler turns on.  I understand that we need the schematic, but...Now we know that the fault is on 12V output  Perhaps an illumnated soul will give hope and light over  this PSU in the next weeks, months...years....