Tutorial How to Modify a Server Power Supply for 12v

G'day and welcome to my first tutorial.

I did a lot of searching but did not find one common document which made it easy to see how to modify the HP power supply for my simulator motors.

Hence I thought I would put one together with plenty of photos for anyone looking at doing this.

Firstly after reading much advice from people on this site I settled on the following power supplies (one for each motor)



This power supply is a DPS-600PB B which supplies 575W(Max) It's input is 100-240V so good to use in many places and can be found on ebay with ease and only costs $15-$30 each.

http://www.ebay.com.au/itm/HP-Proli...ver_Power_Supplies&hash=item2330a04cb6&_uhb=1



So the first thing to point out is the connectors on the power supply board. Some people open up the unit and take this connector off to solder direct to the board.

I'm going to show how it can be done by anyone with limited skills and is also very quick and easy.

The connectors that we require are as follows;



In order to get solid stable voltage we will join both earth connectors together and on the other side we will join both +12v connectors together.

In the middle there are a number of pins which control the unit. We are going to join pins 4 and 8 which will lower the fan speed to a much quieter level (about half) and provide ample cooling for the the unit. If the unit begins to heat up the internal controller is still able to increase the fan speed itself so this is a great modification to do.

Then join pins 6 and 10. This, when also joined by pin 8 via a switch will turn the unit on (it will make more sense shortly) I chose to put a switch in place for a couple of reasons - one it will look good on the dash of my simulator and two it provides easy control over power to my motors etc.

Solder wire to the main voltage pins. I used a RC (remote control) silicon covered wire which is rated to 600 degrees and 600V, easily available on ebay.

http://www.ebay.com.au/itm/AWG14-AW...faultDomain_15&var&hash=item258c7d2916&_uhb=1

I have wired one long wire (for the motor +ve) one shorter one for other accessories requiring +12v in the future and a short link to join both connectors.

Then make it safe and look neat. Heat shrink is your friend



Rinse, wash and repeat (joking) and do the same for the -ve (earth side)



Next - the pins in the middle are very small and to some may appear like they are going to be to hard to use/solder etc. Well there is a very easy way. RC servo connectors. These are also available on ebay, however if you have ever used remote control cars/planes/helicopters you may have some lying around like i did.



Cut the connectors off leaving long length of wire



Separate the wires



You will need 3 (three) connectors in total.

Connector 1 (one) - remove the middle pin only using a pointed tool to lift the retaining tab.



Connector 2 (two) - remove pins 1 (one) and 3 (three)



I actually removed all three pins and replaced the middle pin with the black one so it matches the colour of the wire it will join with on connector 1.

Connector 3 (three) - Remove pins 1 (one) and 2 (two). Again I removed all pins and replaced pin 3 (three) with the correct colour wire. you dont have to do this but it looks better and is easier to follow.



Next you glue them all together. I used a very fast drying CA glue used for RC car tyres. You can use any glue just dont use very much and dont get any inside the pins!



I then twisted the same colour wires together and used some more heat shrink to tidy it up, and there you have your middle connector!



Now you can plug that into your power supply. Remember the wires should match the pin diagram back at the start - the top connector should have two wires in it.



I then join the two black wires together and the two white wires together and put them on a switch. This will then turn the power supply on and off (output). The internal fan is always on when power is supplied to the unit (input).




All that is left to do would be to extend the switch wires and mount the switch somewhere on the dash and connect the output wires to the JRK's or whatever you are powering.

I hope this is useful to you and easy to follow.

Thank for reading,

Slider

Wire gauge on the RC Servo motors is unknown - could probably look it up but it does not carry any significant current - 5v max.

For the main cables 12-16 gauge would be fine.

Very good effort @Slider ... That's really smart and with a good pictures too ...

But after you measured the output voltage ... where are the other terminals for the 5v and the -12v ?

Good tutorial!

I used the same for my 2DOF without any problem!
Here another tweak

Servo Awg wire depends on the Brand/Level of quality.

This will more than do the job, So you can refer to it as 22awg.

http://www.hobbyking.com/hobbyking/..._Servo_Lead_Extention_JR_22AWG_5pcs_bag_.html




PS Awesome write up, Mine have been near flawless since i got them.

Here is another pinout reference for server PSU
Dell poweredge 1850, 2800, 2850, 2950, AA23300, NPS700AB, N750P-S0

Connect PS On and PS Kill on Ground to power up!

These 2950's are Bad A**, 750W @ 62.4A


Little tip, DO THE FAN MOD, That is unless you want the sound of a JET FIGHTER coming out of your PSU, Lol

Seems Ipsonlineorder1 has a steady Supply of these 2950's and for 30$ for a pair, I think that's a pretty smokin deal. I have dealt with him a few time's now and Quick shipping with Really well packaged PSU's All bubble wrapped and Swimming in Popcorn.


http://www.ebay.com/itm/Lot-of-2Del...=US_Server_Power_Supplies&hash=item3ce9318f16

take out your ADD, OCD, ADHD on the bubble wrap and smoke the popcorn

Thanks for the heads up @Nick Moxley! Even though i plan to power my sim with a large deep cycle battery it seemed like a good deal so I ordered a pair.

$ for wattage, there pretty hard to pass up for any North american buyer, Turns out we obviously have a rather "Hot" market for these used PSU's vs a lot of other parts of the world which Dont have access to these bad boys. I look forward to seeing what you think of them, There rather Beefy units @ 5lbs a pop.

Hey @Nick Moxley just ordered some for me and my brother (our 450watts just aren't up to snuff for 100% power output and keep tripping.) Can you give me a little more detail on what you did to your fans? Did you swap them out or did you lower the fan speeds on them. PSU fans at max are entirely too loud haha

Use the pin out and while shorting the PS ON and the PS kill to gound to turn it on, Ground out the fan wire as well. I just left the 2 pig tails which i then attached some RC connector's to have the PSU's removable from the wiring up to the kill switch.

I purchased a couple of these, modded one all up, ran it with a Motor Monster, Arduino and a 180W crab pot motor, everything seems to work but the power supply is sounding an alarm of some sort, a high pitch tone -- any ideas?

@substatica - are you sure it's "tone" sound and not a high pitched screech? The reason I ask is that you might have a leaking capacitor, or one about to give up the ghost.
A test you can do is take power from the PSU and listen to the PSU carefully, and if you hear a slight "pop' sound it might well be a bulging capacitor popping back as it slowly discharges.

Upon testing a second time, it seems to be coming from the motor, not the power supply (I had thought power supply since I'm used to PC and servers beeping error codes), a high pitch whine, video below. Is this normal for motors? or new motors at least?



For now I'm just sending it a simple Arduino sketch to turn one way,

Code:

analogWrite(pwmpin, 80);

When the motor is off it does not spin freely, no. I'll try direct power tonight. Some of the Arduino sketches I've seen read a current sensor from the Monster Moto, no one here seems to talk about that (or wire it) what's a safe PWM max to send?

Some reading makes me think it may be the PWM frequency, anyone else experienced this?

http://forum.arduino.cc/index.php?topic=188309.0