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I currently have four raspberry pi's connected via ethernet to each other. They are currently powered by four 1A power adapters which works fine. But I was wondering if there are any devices out there that can supply enough power through usb to power the devices from a single power source. All the usb hubs I've found so far only provide a maximum of 500mA, which isn't enough.

If anyone has any links to something on amazon or ebay, that would be excellent.

Edit

Although for the moment I only need 4 high power usb ports, in the future I will be introducing more pi's to the system. So if I can add more devices per hub, then that's even better

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    This hub can power a RPi, a passive HD, a wifi dongle and a wireless keyboard/mouse dongle. It comes with a 2.4 A power supply. It should be able to power 3 RPis. Lesson 1: 3 suitable power supplies may be less expensive than one USB hub. Lesson 2: "non-working" USB hub with a sufficiently powerful power supply can still be used to power RPis as long as the USB port of the RPis are not connected to the USB hub. Jan 19, 2013 at 19:47

4 Answers 4

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If you don't have a problem using a soldering iron for an afternoon of nice DIY, I would suggest buying a 5v regulated power supply, like these on ebay, in combination with some wire and these connectors or similar and you can add a great amount of RPis to one supply. For example the 40A supply that is on the top of my list would have no problem at all to power 40 RPis. You'll be done for a little over 30 USD.

Hub

You are not going to find USB2.0 HUBs that officially supports more then 500mA per port, for the simple reason that 500mA is the maximum power output for a single USB 2.0 port according to the USB 2.0 specifications. In reality however many of the USB Hubs just connect the input power supply to all the output power contacts of the various USB output ports of the hub, meaning that you could dissipate the full power of the Hubs power supply over one port. But for this you need to open the Hub and see if it is constructed like that, if so you can also add a bigger power supply to the Hub itself and dissipate 1A per port without problem, BUT AGAIN: You need to check this on a PER HUB basis!

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    Yeah, thought I would have to go down the DIY line, I will probably be following this myself, and would also be the cheapest option. Was wondering more about existing products, but at that growth rate, it does seem like an up hill struggle
    – topherg
    Jan 19, 2013 at 13:40
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    If you want you can do it even bigger, for example Meanwell sells 1500W 5V regulated power supplies, that gives you a respectable 300A on 5V. But being a high quality brand I don't think ebay sells those, and they are not cheap. And connecting 300 RPi's to one supply has its own problems, the power distribution itself.
    – ikku
    Jan 19, 2013 at 14:09
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    lol, i think that might be overkill. I think I'll stick to only having, maybe a maximum of 20 RPi's per device, then it's only 100W per plug. that's not too bad
    – topherg
    Jan 19, 2013 at 17:15
  • @ikku From a health and safety point of view - when dealing with such large PSUs take off all rings, jewellery, wrist-watches etc. for anything that may come in contact with terminals - even though the voltage (5V) is insignificant the current that can flow from shorting out "live" terminals is enough to heat up and melt many metals (and the ones that don't are just going to cook any flesh near them)...!
    – SlySven
    Jan 16, 2016 at 13:42
  • Things have changed. There are now plenty of hubs that put out all sorts of amperages for fast charge smartphones, tablets, and other devices that charge via USB. Also, we now have USB 3.0 which puts out 900mA per the spec, so you know there is more mA available if it's hacked or made that way. Apr 4, 2016 at 19:28
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The cheapest way to do this is to get an old ATX power supply. The specs on the box should get you the max current on +5V.
http://en.wikipedia.org/wiki/ATX#Power_supply
connect pin 14 to 13 to switch on. Pins 4, 6, 21, 22, 23 give +5V.
24 pins connectors means 3 +5V more outputs as ATX 2 was intended to adress the growing demand of that voltage on post 2000 CPU/motherboards.

To power the Pis, I would recommend to solder some USB sockets, and use standard cables, rather than cuting the cable or soldering micro-USB plugs.

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  • Ooh, I like your usage of an ATX psu instead of a high wattage 5v reg
    – topherg
    Jan 19, 2013 at 13:44
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    Be careful with minimum PSU load issues - PC PSUs may not regulate the their output voltages very well if the load (of just a couple of RPis) is not enough - the voltages can rise so much that it blows the polyfuse when the 6V protection diode (D17?) conducts or the rest of the Pi.
    – SlySven
    Jan 16, 2016 at 13:48
  • Keyword OLD. Older ATX PSUs had more power available on the 5V rails, but newer ones have more power available on the 12V rails. Apr 4, 2016 at 19:27
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I know I'm a bit late to the party, but I've also been looking for a high power 5V solution. After reading about how terrible knockoff power equipment can be, I was a bit skeptical about buying what ikku suggested on ebay.

I found this from Adafruit, which should be a solid product. It's a bit more expensive at $25, but power supplies aren't something to skimp on. You would need a breakout for the plug on the end of it.

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  • +1 Doesn't matter if your late to the party, that is a very useful point. Fortunately, the one I got that was similar to the one's ikku suggested has so far not done any damage/exploded/had any other problems, but as much as that adapter is more expensive, it does appear to be high quality
    – topherg
    Aug 8, 2013 at 17:05
  • Or you could see if that plug fits into a USB hub. Then you wouldn't even need a breakout !
    – Lawrence
    Aug 9, 2013 at 1:34
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I have one of these, and I tested it with a Raspberry Pi B+ and it powers it up. Powers up all sorts of stuff, save for some Windows Mobile PDAs I have. They could just have bad batteries though.

There's all sorts of USB power supplies and testing gadgetry on Amazon and eBay, so you don't HAVE to make something if you don't want to.

I'm not affiliated with Sabrent, but since no one across a few different questions knew about these types of devices, I figured I'd throw in my $.02 (In case you noticed me preaching about these things).

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