Convert Server Power Supply

[mt_100]

I have two server power supplies that were going to be thrown out. I'd like to convert them to bench power supplies if I can, if not bin them. I cannot find any info on the internet regarding the pinouts so I'll provide my findings and see if someone can help. As of yet I cannot get it to power up.

They are Compaq parts and here is the info on them:

Compaq Model DPS-450BB
Series ESP104
P/N: 401401-001
Spare/N: 101902-001

However I opened one up and also see Delta Model number DPS-450BP

They have two connectors on them. One is a 24pin that looks like an ATX 24 pin but has a different wire arrangement. The other is a serial port (RS232) 15 pin connector. Both are built into the back of the case since it is a hot swappable PSU.

Wires on the 24 pin are:

B B B B B R R Br Br Y Y Y
B B B B R R Br Br Br Br Y Y

The serial connector has voltage on the following pins.

8 pins top and 7 pins bottom

0v 0v 0v 0v 0v 0v 1v 0v
.2v .2v 0v .1v 5.2v 5v 1v

[Terry Pieters]

Don't throw them out I saw the info some where in this site. You can get 3v, 5v and 12v some have plus and minus so you can get voltage combinations.
I dont have the colour coding with me but you need to connect two of the wires so switch the system on. And a 12v (car bulb) on the 5v circuit to provide the activating resistance.
You will find the info.

[mt_100]

Yeah, I know.

I have converted plenty of ATX power supplies and know how. If you read the post, these are server power supplies with non standard connections that I was wondering if anyone else knew about.

[dmccormick001]

You're thinking about a regular PC power supply. These are server power supplies.

[Andy W]

What brand and model of server did they come out of?
..a

[mt_100]

They came out of Compaq Proliant DL580 servers but I belienve they also are used in the 6400R servers as well.

[FlynFoam]

mt 100,
This may be of some help.

http://www.hangtimes.com/id45.html

[mt_100]

Let me REITERATE for all the new folks. These are SERVER power supplies, not AT, not ATX.

Update, the RS232 connector has voltage on only two pins. The top row second to the right side and far right bottom row. Top one is about 5v and bottom is about 3v.

I don't think I am going to get them to power up.

[tomahawkflier]

http://www.rcgroups.com/forums/showthread.php?t=1005309

Google is our friend

[mt_100]

Already read that thread and although that PS is a server one it doesn't have the same rear connectors on it.

[dmccormick001]

If you have only the two connectors, a 24-pin ATX style and an RS232, it doesn't sound like your unit has the connectors you would expect to find on a unit capable of delivering the higher currents most server PSUs do. If you look at the other examples of server PSUs that have been successfully converted, they seem to all have some kind of spade or other high-amp connectors on them. Is it possible that the PSUs you have are more like conventional PSUs that supply multiple voltages at lower currents? If so, maybe there's a "sense wire" or something like that similar to the AT/ATX types. Just a thought.

Edit: Oh crap, nevermind. I just saw a picture of this unit.

[mt_100]

Yeah, I poked at them last night and couldn't get a power on. These things should deliver 26 amps. I'll keep poking but I don't think I am going to find the power on signal without a lot of trial and error.

[dmccormick001]

Can you get any clues from taking the cover off of it and having a look around inside it? On the At/ATX style PSUs, at least most of the time, the "power good" wire actually has the letters "PG" printed on the pc board next to the pad to which the wire is connected.

[mt_100]

There is stuff on the board(s) but I don't see indication of the power good signal. Still looking, will look for "PG" as suggested thank you.

[mt_100]

I pulled another one from an IBM today. It's a Delta DPS-250HB and has a flat circuit board connector on the back. I think it is a 24 pin ATX in circuit board form. We shall see.

[mt_100]

Having better luck with this one. I found the two contacts on the board that will ramp up the fan and start the 12v rail.

At the moment any load on the 12v rail causes it to shut down though so I need to try resistors on one of the 5v lines and see if the load will straighten it out. If not then there is something I am missing yet.

I'll report back. Hoping this one will work out since the server it came out of has three more in it. Only a 14 amp but that is enough to run two chargers off of.

[dmccormick001]

Could be that the sudden load on the 12v rail is causing the circuit to think there's a problem and it's shutting it down. Keep at it. If you've got the fan running you're making real progress.

[mt_100]

My thought as well, there has to be something that tells it to load up and get ready for load on the 12v. Maybe some sort of back feed to another pin.

Close, but no cigar!

[Rodney]

My thought as well, there has to be something that tells it to load up and get ready for load on the 12v. Maybe some sort of back feed to another pin.

Close, but no cigar!
Yes, most of the older units all require at least a 5 ohm load on the 5 volt line. Just pick up a 5 volt resistor (10 watt rating or higher) and put across the 5 volt line. You could also use any light bulb that draws at least 1 amp at 5 volts instead of the resistor. Note: this resistor will get quite warm so mount it where it won't hurt anything and can get good circulation.

[mt_100]

Tried a 10 ohm on it and no go. I am wondering if since it is a hot swap unit, and the 12v don't come alive until I bridge the two pins if there is a 12v 'feedback' where it needs to see 12v back on one pin before taking a load on the 12v lines.

Will require finding it and playing around but we shall see. I gave up on the Compaq units I had. If this doesn't work then I'll bin it too.

[rc404]

Having better luck with this one. I found the two contacts on the board that will ramp up the fan and start the 12v rail.

At the moment any load on the 12v rail causes it to shut down though so I need to try resistors on one of the 5v lines and see if the load will straighten it out. If not then there is something I am missing yet.

I had a similar problem converting a regular PC power supply. I had a 5 ohm load on the 5V rail. When I turned it on, it would come on and I would see 12V on the 12V rail with a DMM. But the moment I connected my charger (a Triton) the PS would just shut off and I had to cycle power to get it to come back on. I found that if I just connected the Triton before turning on the PS, it worked fine and I got plenty of current out of it.

I'm presuming a current spike tripped the shut down circuitry. My thought is these PS's are made to start up with a load on them. You might try that.

Ed

[mt_100]

Interesting. Going to try that when I get home!

Makes sense now that you say it since it is a hot swap supply.

[dmccormick001]

But the moment I connected my charger (a Triton) the PS would just shut off and I had to cycle power to get it to come back on. I found that if I just connected the Triton before turning on the PS, it worked fine and I got plenty of current out of it.
Ed
Yep, some chargers have fairly good-sized capacitors in them that charge as soon as the unit is turned on, and the PSU looks at that as a potential "problem" and shuts down. Common problem, and the solution is just what you did, connect the charger to the PSU before you turn it on.

[Koyaanisqatsi]

mt_100, did you ever get the DPS-450BB running? I have a couple at work I'm going to bring home and work on. If you did, let me know how you did it. If not, then I'll figure it out and post what I find. These Compaq/HP server supplies appear to be very similar across models and I just figured out the DPS-450CB-1 on this thread:
http://www.rcgroups.com/forums/showthread.php?t=989028

The 'BB' should be almost identical in operation.

Cheers!
Mark-

[Soarmax]

I have two server power supplies that were going to be thrown out. I'd like to convert them to bench power supplies if I can, if not bin them. I cannot find any info on the internet regarding the pinouts so I'll provide my findings and see if someone can help. As of yet I cannot get it to power up.

They are Compaq parts and here is the info on them:

Compaq Model DPS-450BB
Series ESP104
P/N: 401401-001
Spare/N: 101902-001

However I opened one up and also see Delta Model number DPS-450BP

They have two connectors on them. One is a 24pin that looks like an ATX 24 pin but has a different wire arrangement. The other is a serial port (RS232) 15 pin connector. Both are built into the back of the case since it is a hot swappable PSU.

Wires on the 24 pin are:

B B B B B R R Br Br Y Y Y
B B B B R R Br Br Br Br Y Y

The serial connector has voltage on the following pins.

8 pins top and 7 pins bottom

0v 0v 0v 0v 0v 0v 1v 0v
.2v .2v 0v .1v 5.2v 5v 1v

Just jumper pin 4 and pin 13. That's all you need to do. This is the simplest PS conversion you can do. No resistor or light bulbs needed. It even passed the ulimate test: my Triton Charger. 12V rail with no load: 12.08V. With 3 amp load: 12.04V

Good Luck