I am trying to build a 3D printer farm with the pi, and I need a large USB hub. I found this hub. But don't know how to evaluate if its any good.

Has anyone tried something like this?
Do you have a 7+ port hub to recommend?

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    Check elinux.org/RPi_VerifiedPeripherals for all known-to-work hubs. If the hub in question has an issues with backfeeding, you could just strip the wire a bit and snip the 5Volt line. – Gerben Jun 26 '13 at 15:11
  • @Gerben none of those are cheap because they are branded – GuySoft Jun 26 '13 at 19:16
  • You're asking for 2 mutually exclusive things here IMO. – Lawrence Jun 27 '13 at 6:37
  • @Lawrence You are saying there is no cheap USB hub without backfeeding? I meanwhile ordered this, because someone said it works in the comments. – GuySoft Jun 27 '13 at 6:43
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    Well, snipping the 5V line will definitely work. That 7port hub is the same as the one that I have, and it backfeeds. I should rephrase what I said earlier, there's no cheap 7port hub that will not backpower without modification. All cheap ones don't have proper power regulation to prevent backfeeding. – Lawrence Jun 27 '13 at 8:18

Raspberry Pi boards manufactured in the third quartile of 2012 do not have issues with backfeeding anymore (due to removed fuse), see http://www.raspberrypi.org/archives/1929 and http://elinux.org/RPi_HardwareHistory#Board_Revision_History.

As previously mentioned you can check http://elinux.org/RPi_VerifiedPeripherals#Powered_USB_Hubs for HUBs, but you should be able to safely power raspberry pi by backfeeding it.

Citing from penguintutor post @ http://www.raspberrypi.org/phpBB3/viewtopic.php?f=26&t=17560

Electrically the only different between the supply from the micro USB and the backfeed supply is that the micro-USB has a 1100mA fuse, whereas the USB ports each have a 140mA fuse. There is a diode preventing the USB power from going into the power out of the USB controller, but not so for the USB supply (which is what makes back feeding possible).

So get yourself some nice USB 1.1/2.0 compatible hub and if it is backfeeding, just roll with it. The only issue I can think of, is that some hubs have dedicated "charging" ports which could actually be only ones designed for >1A load.

  • I have both a rev2 and a rev1 PI I can reach. Will test and update you if it works :) – GuySoft Jul 3 '13 at 11:37
  • Got backfeeding from a RAMPS 1.4 board on a rev2 and rev1. It works fine on a PC – GuySoft Jul 20 '13 at 16:49

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