HP ATSN 7001044 - 83 amp DC Server Power Supply 14 volt Modification

These Disposal Server Power Supplies are readily available on ebay for $20- $40 or so, and make excellent high current Battery Chargers, with just a few simple mods. This short video explains the mods with no disassembly of the power supply required. Make is Hewlett - Packard (HP) Model is ATSN 7001044. Please enjoy!

[@click2p]

I found the same power supply in a scrap yard and I didn't know how to start it. Your video solved this problem. Thanks a lot. 😊

[@lmckrosen123]

You, Sir, are a GENIUS!!! I found an old one of these in a rubbish heap and was ready to return it there when it didn’t seem to work. Shorting the second pin on the top with the one on the bottom kicks on the LED and outputs 12 VDC! Next, I’ll complete the mod to output the 14 volts at some point!

[@jirismidak2309]

Mr. Waterson, sir, u made my Sunday! I took couple of those HP PSUs with different wattage from a local company IT waste bin, one of those was this 1kW PSU... which, thanks to you, sir, is now charging my motor bike battery, set up with a 2k2 resistor instead of the trim resistor to 13,63 Volts. Thank you very much!

[@eshahmed6336]

Hi great video. Just done the same and happy days. Needed for programming the BMW. Thanks for your help

[@DougWaterson]

Thanks Esh, I have used this supply for a number of projects. Good value for high current 12 to 14 volt DC power supply applications. Cheers DW

[@oscarmascarenhas5989]

Hi Doug.. Can you show the wiring dia of the resistor and potentiometer.

[@snhongo1]

Great video

[@muhammadasim3162]

I think first of All .I searched its pin to increased voltage 3 years ago And i have a special trick to find pins to increase voltage

[@peteryli2751]

On the pins shown on the related pin-out jumper modifications, there are not the indicated voltages ... WHY ? ... any schematics available of this specific power supply ??

[@sandyskullen254]

Hi, is that a small resistor fitted to the blue wire on the left also, or will the potentiometer work just on it's own, and also is it wired to the first prong and the last prong? prong 8? thx

[@agha2424]

What about amperes sir,are 82 ampere good for charging battery.

[@cowboyinthehawgyard4192]

What value variable resistor did you use please

[@crjcustom]

Do you ever try to nip the volts up on a blade c7000 Hp

[@enginaras2605]

Hello, I have atsn 7001044 but I could not run it. I looked at all the videos and documents on the internet. It works when you plug the device into the server. Could you help?

[@DougWaterson]

Have you followed the video instructions. To turn the supply on you will need to solder a jumper on the two pins on opposite sides of the circuit board as explained in the video. You will then see the green led adjacent to the AC power inlet socket light, meaning you will have around 12.2 vDC at the output, and you will hear the two exhaust fan start running. It works in the server rack because it is designed that way, with the on/off circuit connected to the two pins described. Hope that helps. Doug

[@scottlang8659]

Has anyone had an issue with the PSU not turning on when the jumper is installed. I installed the jumper and it turns on for 1/2 second max. Then when I unplug it the fans turn on after about 2 seconds and run the stored power down. Strange.

[@tabitnabil8771]

i have the same problem do you fix it

[@DougWaterson]

I have not had to remove the cover from this supply, so I have no need to be concerned about charged capacitors, however, I would be very careful if I was to open it up. Maybe discharging the supply with a wire wound resistor or a 12 volt car lamp. No I don't know the size of the fans. I do know they make a fair amount of noise when you draw large currents.

[@SeGin_]

Thanks for the answer! What would happen if I don't use a potentiometer/resistor and just bridge these two connectors with a cable?

[@DougWaterson]

SeGin if you just bridge the 2 opposite pins, you will turn the power supply on and you will have the standard 12 volt output. Only add the resistor if you want higher voltage. Remember that the supply has over voltage protection so it will not increase any more than about 2 volts until the OVP circuit will shut it down.

[@LoLKeK-wk2ku]

hello I will be very grateful if you answer quickly and what kind of resistor did you use for how many ohms ?

[@DougWaterson]

LoL 2004 KeK I used a 10k multi turn pot so that I could use it as a battery charger and vary the voltage from 12v to 14.4v. If you don't use a resistor then the supply will supply the standard 12 volt rail voltage, typically around 12.2 volts.

[@LoLKeK-wk2ku]

@@DougWaterson I have the same two blocks and I feed them to the home music system and for perfect operation you need 14-15 V so I wanted to know what you need for a resistor thank you . and can you still tell me exactly what kind of resistor you need ? so that I can adjust the voltage from 12 to 16 v thank you for your help .

[@roystervi]

I got 2 "DSP-800GB A" I jumper the the 2 2nd pin to verify the fan comes on and it did. However, without the 2 2nd pin jumped I forgot to unplug it and it was plug in over night, the next day it was hot as hell. as it does not have 12v while the 2 2nd pin is jumper, it seem as if the transformer still hums and heat up. can anyone verify this or do I have a bad PSU. thanks in advance.

[@thorbjornkarlsson4681]

The same happend to me. I think its made that way.

[@radian10]

Can you put two of these in parallel and have double the amps ?

[@DougWaterson]

Actually, the short answer is not easily, as some form of resistive balancing would be required if you were to do it properly. If you were prepared to experiment and maybe fry a couple of supplies in the process you may come up with a workable solution, however I really have no need for more than 80 amps, and therefore can offer no advice for you. Maybe others on KZbin have a solution. Cheers Doug

[@snhongo1]

Yes but you just have to put high current diodes on the outputs of both psu ..same as you do when want to bridge more transformers

[@captaininsano2777]

Yes you can. The voltages of each supply needs to exactly the same and wires for the DC side need to be the same length.

[@snhongo1]

@@captaininsano2777 Hie are you saying if there voltages are the same you just put positive to positive and negative the same without diodes and you wont have a problem?

[@captaininsano2777]

@@snhongo1 ive done it many times.

[@manuelguerrero5697]

How do you turn on the supply?

[@DougWaterson]

As described in the video, just solder a jumper wire between the two end connectors that second in from the left (top and bottom, looking front on) or wire a simple on/off switch to the same connectors. That will turn on the supply. Hope that helps.

[@ik6qre]

@@DougWaterson Hi Doug. I have the same PSU. I made the same mod (a short in second pad from the left, top and bottom, looking front) to switch on but mine doesn't run. Neither the funs, nor the green led. I hear only a click and very low hum. The only difference between mine and yours ATSN 7001044 is the HP rev. I got the "J". You the "M". Any suggestions? Thank you.

[@milkman5038]

@@ik6qre i have same problem- shorted those two pins but if it turns on just for second or two and tested voltage jumping 0.3-3

[@ik6qre]

@@milkman5038 In my case no activity. Just a small internal click and a weak hum. Few millivolt at the ends. Hoping for a Doug's help.

[@augustmarindang7949]

@@ik6qre mine also like that case.cannot turn it on

[@dennis1161]

ta5fa.blogspot.com/2019/05/atsn-7001044-psu-test.html why you connect resistance not like here?