How to build a $20 47A power supply

[radioman193]

i needed 90 Amps
for the sound in here...
and 110amps when im pushen it but it still wants more
so i use a 750cca battery when i want full power.

for my custom Moded amps on
6 Main's
and a pair of Shocker 12" Apocalipse woofers
in a custom folded horn enclosure.





I miss my Sound off's / IASCA and IdBl

[bryan]

Nice fan

[radioman193]

it was before i got the ac in back here and it was over 100 that day and only went down to like 91 or 93 that nite.
so the old junk fan was the best way to keep things cool.
plus the amps dont dissipate heat well with the builtin fans mounted vertically on the wall like that.

but there happy now.

[slimthelineman]

sweet setup!

[radioman193]

Thanks ...

its part of my pirate radio station controle center for
88.9 Thunderground radio.


500Watt stereo @ 88.9 Fm.
Real Radio no web streams.
its Been on the air for 7 years now

i got all new 22" Monitors and well ill just say its been All upgraded from when these pictures were taken.........

[snellemin]

very nice setup man

[Metallover]

Tonight when I was charging my 6s 30ah pack, my Hyperion EOS0610i charger failed while running off of the HP power supply in the OP of this thread. I doubt it was the PS's fault, but I thought I would post it here just in case. I was kind-of pushing the charger, but it hasn't failed after months of use until now. Also, I have lost a power supply charging this pack too; maybe my main is the culprit..

To fix this problem I just bought two more power 575w power supplies for $26. I'll mount two on some plywood and wire em up for 24v to run a new charger... Maybe a 1000w charger to charge my 6s 30ah pack??

[florianz]

hi there,
I am trying to get an other power supply, and have found an p/s "750W p/s ASR2500PS Intel Modul for SR2500". it supplies 62 amps (!!), I just wonder where to connect what... it looks a bit different than the HP serverer power supplies.


I have three chargers (average stuff) on one pc 500w p/s and sometimes it seems not to be sufficient.

otherwise I am going to get a 800w PC p/s, it may be a bit easier for me, 'cos I have already converted one. this server stuff is new to me...
edit:
this one might be an alternative:


many thanks
florian

[BrianG]

That 750w supply is only good for 20A on the 12v rail. However, from online documentation, it also has a -12v rail rated for 20A as well. If true, you could get 24v @ 20A from that...

[BrianG]

Originally Posted by Metallover

...To fix this problem I just bought two more power 575w power supplies for $26. I'll mount two on some plywood and wire em up for 24v to run a new charger... Maybe a 1000w charger to charge my 6s 30ah pack??

I would be surprised if that works. More than likely, both supplies share a common ground, and when you hook them in series, you will short out the output on one of them.

[florianz]

hm, on the sticker it says:


what do you mean, is it possible to "add" voltage?

[BrianG]

Well, that's weird. I did a quick search and the stickers I saw didn't say that. It should work fine then.

If you have a positive and negative supply rated for the same current, you can hook up your load across the two; load+ to supply+ and load ground to supply-. You see that all the time with regular power transformers: you'll have your main outputs, but then also a center tap. If you use the center tap you get a + and - supply. But if you just use the main outputs (not center tap), you get the full voltage. RadioShacks transformers are like this. Like their 12v models; they're rated 12.6v, but if you use the center tap you get +6.3v and -6.3v.

[Metallover]

Originally Posted by BrianG

I would be surprised if that works. More than likely, both supplies share a common ground, and when you hook them in series, you will short out the output on one of them.

I saw earlier in this thread something about it...

Here's good how-to on converting two 12v power supplies to one 24v power supply - http://www.rcgroups.com/forums/showthread.php?t=1164359

[BrianG]

Originally Posted by snellemin

I figured I post this up for you guys that want an affordable 12.5V 47A capable power supply to power your chargers.

The model number is power supply in question is 321632-001, DPS-600PB HP 575W Power Supply Proliant DL380 G4. All you need to do for the PSU to "Turn on", is short 3 connectors. Basically two hot wires to ground. No load resistor is needed.
When you look at the back of the PSU, you'll find 4 blade plugs. The two on the left are ground and the other two on the right positive. In between the blade plugs, you'll find a set of 12 pin connectors. You'll see a pin that is shorter than the rest, which I call pin 6.

1 2 3
4 5 6<---short pin
7 8 9
10 11 12

Connect 6 and 10 to 8(ground). I believe pin 5 is ground as well. Note that the PSU fan will turn on when you connect it to the AC line. The fan will speed up, once you short the 3 pins together. I opted for plugs to the pins, but you can use a switch instead. You can use servo leads as well.

Solder your power wires to the blade pins and have fun charging.

I picked one of these up for $25 shipped and it came in today. And of course I opened it up as soon as I got home. Bad news is that there is no adjustment pot inside; I even looked under the heatsinks. The good news is that I was able to boost the output to 12.95v. Not much, but still some.

All I did was create a voltage divider consisting of a 220 ohm resistor and a diode. Tied the + output to the resistor, the other end of the resistor to the anode of the diode, and the cathode of the diode to the - output. I then tied a wire from the diode/resistor connection to pin 5, which feeds ~0.7v to pin 5. Looks like pin 5 is not a ground, but a feedback line to boost the output if there is voltage drop due to heavy current. This resistor/diode trick just tricks the PS into thinking it needs to output higher voltage.

[snellemin]

Good stuff Brian.