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While having nice little single-purpose machines is great, I have a proliferation of wall warts now which is becoming untenable. Between a router and an ethernet switch and a HDMI switch and a USB hub and an external hard drive PSU and that's just directly related to the Pi - I also have a Pogoplug, a Roku, a Micca and a powerline ethernet bridge also in the same area.

Anyone building or buying solutions to output DC to all these devices from a single large PSU instead of a monster power strip(s) handling all the wall warts?

I just did an inventory:

12V X 3
5V (1 is 5.2V) x 4 (counting the Micro-USB for the RPi)
7.5V x 1

I found this similar question, but it has no particular guidance on specific approaches to selecting a power supply:

https://electronics.stackexchange.com/questions/25026/combining-multiple-ac-dc-adapters

This might be a great type of project to embed an RPi (or similar device) within:

http://pwnieexpress.com/products/power-pwn

  • Hmm.. Model A can be powered though a USB hub.Don't know about the rest. – ArchHaskeller Jul 22 '12 at 18:20
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    British citizen here... What is a wall wart? – Alex Chamberlain Jul 22 '12 at 18:23
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    @AlexChamberlain AC adapter. – ArchHaskeller Jul 22 '12 at 18:25
  • Are they all 5V? – Alex Chamberlain Jul 22 '12 at 19:06
  • @AlexChamberlain No, I added the voltages here, but I'll have to do more digging around to find the actual current draws. – Cade Roux Jul 22 '12 at 21:46
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Personally speaking I try very hard to only buy 12V or 5V devices, and then I create adapters to run them off a PC power supply. Then you can either connect them to your PC so they switch off when you switch your PC off, or you can buy a cheap PC power supply and leave it running 24/7 without connecting it to a computer.

You would need a certain minimum number of devices to make this worthwhile - if you think a bunch of power adapters look bad, a bare PC power supply isn't much nicer. In my case all my equipment is in a standard 19-inch rack, so at least I can hide the supply somewhat.

This isn't a quick solution though. You have to be willing to solder up custom power cables for each new device you use (since they all seem to use a slightly different power connector) and you need to build junction boxes or similar to split a single power rail into multiple power cables, one for each device.

You'll also have to come up with some solutions for devices that require non-PC voltages, like 7.5V. Don't be fooled into thinking you can do the trick often done to run fans from 7V though, where you use +5V as GND and +12V as VCC. When you start connecting devices together with shielded cables the shields will connect all the GND lines together, and suddenly you're shorting +5V to the real GND via one of these cables. This will either short out the power supply (which will promptly switch off, no harm done) or more likely it will deliver a substantial current across the cable making it get very hot, and possibly melting the insulation. To do this correctly you can often get away with a voltage regulator, since most devices like this only require small currents.

If you're only looking at a simple way to power your Pi and all its peripherals, maybe an old PC case would be the way to go. They're easily come by (often for free), there's plenty of space to mount the Pi, USB hub, and even internal hard drives, and if you've got an older LCD monitor that runs off 12V then you can even power that from the case as well.

  • Do you have any pictures of a unit hooked up to a PSU as you've decribed? – Zoot Jul 23 '12 at 14:20
  • @Zoot: There's not much to see. Just a black cable going from a PC, out the back and into a device like normal. – Malvineous Jul 23 '12 at 23:30
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Well, you don't have to power the Raspberry Pi using the micro-usb. Therefore you could just attach power from a PSU, so long as it could provide the correct voltage and current.

Sorry I cannot answer about your other devices, I know only about the Raspberry Pi :)

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I did some research, but concluded it was too expensive. Meanwell has some nice DIN rail supplies that could work for about $15 each.

There are distribution blocks such as this one: http://www.hometech.com/hts/products/wiring/struct_wire/leviton/miscellaneous/le-48212dc.html?key=A27&pk_kwd=LE-48212DC&gclid=CO316PrwyrYCFUWo4AodgEEA5Q

and even this one: http://shop.willyselectronics.com/browse.cfm/9-ch-addon-cctv-power-supply-expansion-module:-9-outputs/4,10850.html

The harder and more expansive part was the case. I wanted to go with a clear polycarbonate face, DIN rail mounting, a breaker on the side. Strain reliefs for each of the cords.

As you see, things get expensive really fast and not much more convenient.

So, I went with an octopus cord and a shelf. It has made my network much more reliable.

At a minimum, i would want a light for each and a fuse for every device, so it can be protected at whatever it needs to be.

Honestly, I'd like the voltage and current to be programmable at the connector.

The missing link for connectors: These are always a possibility. Connectors

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I bought something similar to this product at my local dollar store for $2:

enter image description here

The nice thing about these is that they have a pass through plug where it plugs in so you can plug in a normal plug right off the power bar, and then plug the wall wart into the extension part, so it doesn't interfere with other things being plugged in. Buy 2 or 3 and you can cheaply convert your regular power bar into one of those octopus power strips.

  • I've got a bunch of these. One of the things is the amount of space (and not just the sheer volume, but the gangly spread-outness) all this takes up - the powerstrip, the cables, the little boxes. – Cade Roux Jul 23 '12 at 15:12

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