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I have an Orico 10 port USB3.0 powered hub that I bought a while back, and have recently come into possession of a pair of RPI2 Model Bs. I was wondering how the "power distribution" on hubs worked; and if I could power my Pis via the ports on the hub, or if the power output would fry my them. The power adapter for the hub has a 110-240VAC input at 50-60 Hz and outputs 12v at 4 amps to the hub itself.

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Most likely yes

The product spec reads:

The ten port model features a 4 Ampere power supply, while the four and seven port models come with a 2.5 Ampere model. This allows up 900mA per port for several, but not all ports at the same time. Typically users have a mix of 900mA, 500mA, 300mA, and self powered devices attached to a hub.

So unless there are more really power hungry peripheral devices connected to the other 8 ports it should be possible to drive two Pi.

The FAQ at raspberrypi.org states a "recommended PSU current capacity" of 1.8 A for the Pi2B. This includes 1.2A to downstream USB peripherals connected to the Pi. So if no power hungry devices are connected to the USB ports of the Pi the 900 mA should suffice to power each.

Because this power consumption statistics have been brought up in another question. Their measurements suggest a current of 800-1100 mA (~4W) for the Pi2B under full load. Well that should make one at least think twice. As always this boils down to how reliably the hub limits the current on its ports (many don't do a good job in sticking to the spec).

  • What about the voltage for it? I know that the Pis only need 5v to run, will the 12v supply burn them out, or do they only draw the 5v they need to run? – Joshua Napier Nov 28 '15 at 21:35
  • Hmm, would be very, very strange if a USB hub outputs 12 V to its downstream ports. That wourd burn all devices plugged into it. You're sure the supply is the right one? The product page lists "Power Supply Output: 5V @ 4.0A (10 port)". – Ghanima Nov 28 '15 at 21:41
  • The label on the power supply lists its output as 12V---4A – Joshua Napier Nov 28 '15 at 21:46
  • In that case I'd recommend to not plug any peripheral devices to the hub, including the Pi. Double check the supply, check the hub's data sheet, is it really the supply for that hub? Sounds weird to me. Sure it's technically possible that the hub would include a step-down converter of its own - but how likely is that? – Ghanima Nov 28 '15 at 21:54
  • There is no datasheet for it, courtesy of Orico. I looked at the webpage for the controllers (VL812) for the ports, and it says they have a 5V DC-DC switching regulator. Could that restrict the output of the individual ports to 5V? – Joshua Napier Nov 29 '15 at 1:17

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