Power Through USB Hub
Kill a few birds with one stone as it were - power for the Raspberry and provide extra USB expansion?
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@grumpyoldgit since the micro usb port only contains the pins for power, it is not possible to use it for data transefer, so in theory, you should be able to power it through one and then plug a male to male usb cable to be able to use the other ports for things.
However you have to keep in mind that the model A requires 500mah and model B requires 700mah, so make sure the usb hub is capable of supplying sufficient power. From what I"ve seen, most hubs only give out 500mah, if you can find one that can give 700mah or higher (the rasberry pi will only take as much power as it needs) you should be ok.
Also make sure to check how much power the devices you plan on using require, usb memery sticks should be ok, but portable HDD"s will have problems, however external HDD"s have their own power supply.
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All you have to do is power the hub, and then provide a connection not only from the R-Pi to the hub (for data), but from the hub to the R-Pi (for power). There is no "loop" to be worried about, it's all at the same voltage and with the same polarity; a properly designed hub will not feed power back along the data cable anyway.
With a typical 4-port hub, you will then be left with three powered ports on the hub and the remaining low-power port on the R-Pi. I strongly suggest using the former and not the latter.
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@ BlueClogger +1
With the concerns over the “Loop” it should be noted that when you purchase your power hub, you will be provided with a cable with 1 type a plug and 1 type b plug or other (not a). This links the output of the Pii to the input to the hub, thereby avoiding any contention.
IMHO this thread has now run it's course.
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