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Old Dec 04, 2010, 11:23 PM
pluto_26 is offline
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COnverting Server Power Supply - EMERSON


I was able to get a couple of these power supplies and would like to convert them.

This thread has been very helping but I still need a little more help to get it to work fully.

The power supplies are: rated at +12.v ---- 55.0A MAX
at +3.3Vco -- 0.2A MAX
EMERSON Module 7001484-J000 or
ACBel FS7923

These were removed from IBM X-Servers.

I have attached a image of the connections 8 signals top /bottom

01 02 03 04 05 06 07 08 P-P-P-P-P-P-P-P-P <--Top
09 10 11 12 13 14 15 16 p-p-p-p-p-p-p-p-p <--Bottom

if I short 07 and 15 the fan starts but as soon as I place any real load 2amp
or more the power supply shutsdowns. I do get a reading from the power pins between 12.2 - 12.4

when I try to get readings of these pins these are teh readings:

Top
01 02 03 04 05 06 07 08
G 4.2 G G 4.8 G G G G = reading 0.0 V

Bottom
09 10 11 12 13 14 15 16
0.2 G 0.2 G 0.1 4.6 4.6 4.6


Electricity is not my thing, understand the basics

ANy help or suggestions on what to try or how I can determine the pins would be greatly appreciated.

Thanks
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Old Dec 05, 2010, 02:28 PM
Marion is offline
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Some computer power supplies require a sizable load on the 5 volt line for proper operation.

I use 3 or 4 10 Ohm, 10 Watt resistors, all in parallel connected across the 5 volt line -- between the red and black wires. Hope this helps..
Old Dec 06, 2010, 09:39 AM
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You mite want to go to www.wikihow.com/convert-a-com...b-power-supply pretty good article , should be all you need .
Old Dec 06, 2010, 06:56 PM
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thanks, that site focuses on ATX power supplies I am trying to convert a server power supply. seems to be just enough diferrent.
Old Dec 08, 2010, 03:56 PM
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Does anyone know ow to test the pins and what pins based on voltage I should try to jump?

I seem to be missing a third one to keep the load.
Old Dec 09, 2010, 05:19 AM
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there are some good threads here for the HP server PSU's
Old Mar 27, 2014, 04:04 PM
Maddin123 is offline
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Hi, I also have one of these PSUs here and no idea about the pinout.

Is there something new you have found out pluto_26?
Old Mar 27, 2014, 05:46 PM
Mike Dubovsky is offline
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I am a nice guy! Really!

A better place to look.


This thread may be more informative to your questions

https://www.rcgroups.com/forums/show....php?t=1292514
Old Mar 27, 2014, 07:51 PM
Maddin123 is offline
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I've figured it out. Top row, pin 1 and 2 and you will have stable 12V output.

I've just tested it with 2 chargers, each 150W, no problems so far.


Many greetings from Germany
Old Jul 10, 2015, 04:01 PM
doug.wagner is online now
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Quote:
Originally Posted by Maddin123 View Post
I've figured it out. Top row, pin 1 and 2 and you will have stable 12V output.

I've just tested it with 2 chargers, each 150W, no problems so far.


Many greetings from Germany
What does that mean?
"Top row, pin 1 and 2"...do you short them together?
Connect with a resisitor?
Find 12V across the pair?
Old Jul 24, 2015, 08:56 PM
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I can fix that!
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Emerson 7001484


I finally got the stones up to try shorting upper pins 1 and 2 together, and sure enough, the LED labeled DC turns on (on the back), the fan turns on (very low) and there is +12V on the large copper pin, on the topside of the connector. Ground is at the large copper pin on the underside of the connector.
Right now I am charging four 3S batteries in parallel, at 12A with no apparent problems.
I think I'll put a small switch between pins 1 and 2, to use as an off/on switch.
Old Nov 30, 2015, 04:54 AM
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Doug... I have two of these supplies. Do you have to put a 5v load on? Can you give any more info, or photo's?? I can understand (mostly) the diagrams, but a photo would be brilliant Many thanks
Old Nov 30, 2015, 09:31 PM
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Quote:
Originally Posted by lainchir View Post
Doug... I have two of these supplies. Do you have to put a 5v load on? Can you give any more info, or photo's?? I can understand (mostly) the diagrams, but a photo would be brilliant Many thanks
Here you go, they're not too pretty, but as good as I can do with my crappy Kodak camera
No, a 5v load is NOT needed to turn it on.
It really couldn't be simpler.
Four wires soldered to the PS's connector board. (OK technically 6, because I soldered a 12V LED strip across the output, so I could be certain when it is turned on)
The 2 thin wires from the off/on switch are soldered to the 2 endmost pads at the left. The +12V output is soldered to the large pad at the right, on the top of the board. The -12V is soldered to the large pad on the bottom side of the board.
HTH
Old Apr 21, 2016, 02:47 AM
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I found one of these in the recycle pile, it's my new favorite power supply. Very quiet, the fan ramps up from almost silent as the temperature rises. I soldered a pair of wires to an XT60 on the output pads and tied the second pad to the far left to the one just to the right to turn it on. I've been using it on my 400W charger.
Old Apr 24, 2016, 03:37 PM
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I spent some time yesterday working on this PSU to determine if it could be modified for series operation for 24V. It turns out it can, although it's not quite as straightforward as some of the others but given how quiet and compact these are I think it was well worth it.

Internally the unit is split up into two separate boards. A small one on the input side holds the input filter and the status LEDs while the main part of the power supply is on a second larger board and the fan sits between them. The DC ground connects to the case through the two screws at the output end so I isolated these by placing several layers of polyamide tape over the bottom of the pads and then replacing those two screws with nylon screws.

Now is when I discovered that the status LEDs are grounded through the case rather than having a separate DC ground in the cable that connects between the two boards. If you ignore that, the LEDs don't work and stray currents confuse the protection circuitry and cause the power supply to shut down. Unplugging the LED cable is a possible solution but then you lose the LEDs. The input filter/LED board is multilayer and of course the LEDs ground to the middle layer so you can't simply cut the trace. What I ended up doing was desoldering the LED assembly, bending over the cathode pins of the LEDs and soldering a wire to those. I put a piece of polyamide tape over the original ground pads and soldered the LEDs back into place, then connected the new ground wire to the now-floating DC ground on the main PSU board. I buttoned it all back up and verified that I now have a floating DC ground and the power supply works perfectly in series with another. It sounds more complicated than it is in practice, having worked out the details I think I could modify another one in 20 minutes.

I ended up buying several more of these on ebay for only 8 bucks each shipped. I love these things, they're super compact and exceptionally quiet, under light load they're almost silent! In comparison my Dell 700W PSU sounds like a hair dryer even with the fan as low as it will go.


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