Repairing YM-3591AAR power supply (HP P/N 81-00000051)

[shahrukhntdc]

Hi Alexij!

Thank you for the prompt advice. Actually/ Unfortunately Ebay/ Amazon etc do not provide services in Pakistan. Somehow I have to go for self diagnostics and repair. Please let me know if you find any other good supplier.

Regards.

[Alexij]

Hi!

as you may guess Russia  is also a member of "restricted  list" for some US  sellers. Not a problem. There are  many "transit" forwarders (for example from Germany) who offer their stock as a destination address. Then they re-send the shipment practicaly anywhere with a quite reasonable fee.  I have a positive experience with such forwarder. Try to find one who works with your country. 

[Tom42]

I am experiencing the same issue as in the OP (intermittent overvoltage alert, now getting permament). [The SAN is a dothill 3000, identical to HP unit].  Haven't yet tried to repair it. Will give it a go after finding this thread.

Apart from the OVP issue it looks like the current balancing is not perfect. The CLI outuput from "show sensor-status" returns (5V Voltage "Error" is due to the wrongly measured voltage exceeding 5.52V. 5.52V was the highest reading I saw before the error turned up):

0 Voltage 12V Loc: left-PSU 12.06 OK
0 Voltage 5V Loc: left-PSU 5.10 OK
0 Voltage 3.3V Loc: left-PSU 3.64 OK
0 Voltage 12V Loc: right-PSU 12.09 OK
0 Voltage 5V Loc: right-PSU Error
0 Voltage 3.3V Loc: right-PSU 3.65 OK
0 Current 12V Loc: left-PSU 6.40 OK
0 Current 5V Loc: left-PSU 6.36 OK
0 Current 12V Loc: right-PSU 9.85 OK
0 Current 5V Loc: right-PSU 4.38 OK

Current balancing is off for 12V (6..40 vs 9.85 Amps) and 5 V (6.36 vs 4.38 Amps) respectively.

Is there an additional problem. How perfect is the current balancing supposed to work ?

[Zdomici]

The current balancing problem could have several different causes. But my first bet would be it's also caused by components that cracked due to the putty. The monitoring circits are quite complex and may report a problem even if the PSU itself works fine, like in my case. Another source of the problem could be bad current sensing resistors. If memory serves, they were on the bottom side of the PCB, with large amount of solder around them. You could test them by soldering thin wires to them and then comparing their actual voltage drop when the PSUs are running into load.

[Alexij]

Hi, folks!

I've found that fans are feeded via separate 1A fuses. At the same time the required current for one fan according to the lable is 1,6A. So if you hear "W-WW-WWWWW" after powering on the device it means that ONLY one fan is running and it is trying to "autorotate" the second one. Just replace the broken fuse of the second fan and enjoy your refurbished PS.

[Tom42]

@Zdomici and @Alexij, thank you very much for replies.

I can confirm that the PSU reporting the "Error" is actually woking and delivering correct 5.1V. Maybe the Amp readings are also just wrong..

I bought a third PSU from ebay to get at least 2 units working. Received it a few hour ago,. This is a Rev. B unit (Datecode 1118), which is apparently working (from the LED status and output voltages). Haven't put it into the SAN yet. The R441 in the Rev. B uses also the 83B value for R441 and measures 4.2kOhm accross. Anyway I guess the Resistor problem is limited early 2010 units.

Was curious on how the current balancing might work and tried to figure out the function of the undocumented Pins. Here's my current status on those:

o Sense- 12V    o GND     o +3.3V  o GND     o GND    o CPU,GPIO?

o Sense+ 12V    o /Pon    o +3.3V  o GND     o GND    o CPU,GPIO?

o Sense-  5V    o CS 12V  o +3.3V  o +3.3V   o GND    o CPU,GPIO?

o Sense+  5V    o CS  5V  o +3.3V  o +3.3V   o GND    o CPU,GPIO?

The management interface (CPU/GPIO ?) have all the same weak pullups to 3.3V

I guess there are two "current share" Pins CS 5V and CS 12V. They change voltage with different current draws on the respective rail (could test only up to 5A load).

CS 5V:  0.502V+approx. 20mV/A. The first 2 Amps are not indicated (CS 5V constant with I < 2A)

CS 12V: 0.511V+approx. 10mV/A. The first 1 Amp is not indicated (CS 12V constant I<1A. Fans running).

The 12V current share line apparently refers to the total 12V rail current. Load on the 5V rail is also registered on the 12V CS line (since the 5V step-down coverter is supplied from the 12V rail).

My stomach feeling is that tthe current balancing is more of a makeshift implementation, which just somewhat yields "equal" current distribution. 

.

[Liaquat_Ali]

Dear community folks please kindly advise me any suggestions to repair following power supply : Hipro HW-N0330XC Open Frame Power Supply HP J4818A PSU HP-N0330XC. Any reply shall be highly appreciated, kind regards !

[Sunitha_Mod]

Hello @Liaquat_Ali,

Thank you for posting! Since you have posted in an old topic and there is no response yet, I would recommend you create a new topic using the create "New Discussion" button, so the experts can check and assist you further. 

[Liaquat_Ali]

Thanks Ma'am, that sounds like a good suggestion. I will do that. In fact I posted under this heading due to relevancy and I thought the experts who go through this thread will likely read my request too