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Ok so I have not been able to find this specific question on the interwebs.

I am looking for a USB hub that will power the pi and a few other things. I'm not concerned about the over all power rating of the hub but rather the individual ports. I have found a few with 2.4 amp ports but I have noticed in the past the rpi 3b runs smoother on 3.0 amp ports. My question is. Can I simply make a cable that connects 2 of the ports from the USB hub to the one micro USB port on the pi. I know the voltage will stay at 5v. In theory I should get roughly up to 6 amps. I know it wouldn't be good to let the pi pull 6 amps so maybe a fuse for safety but is there anything I'm missing here?

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Yes, you can run as many as you desire USB cables in parallel – the power leads are for all practical purposes already in parallel anyway. Perhaps somebody makes “unpowered USB hub” you could use as sort of bridge / splice gizmo on each end of the cables run.

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  • Power leads are only in parallel on a hub without any protection circuitry (or with a single polyfuse for all ports), at which point the current isn't limited to the specified value anyway.
    – Dmitry Grigoryev
    Feb 8, 2019 at 14:10
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Your question demonstrates a lack of understanding of circuit theory. Connecting multiple ports will NOT increase current.

The Pi will only draw as much current as it requires and the Pi3B+ will run on a 1A supply, unless peripherals require more.

A standards compliant USB2 hub WILL NOT supply more than 500mA, although many are actually non-compliant. The only way to know is to test.

Those which claim to supply more only work to charge batteries on smartphones BUT NOT at 5V (the standard allows voltage to drop to 3.6V), and even then only if suitable negotiation occurs (which the Pi CAN NOT do).

Some others support proprietary standards for specific phones, but are unlikely to work with the Pi.

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    A discussion should not start with putting the OP down. It also presents unnecessary superficial fluff. ( The OP does not need to know USB ports specification for battery charging) Yes, you can run as many as you desire USB cables in parallel – the power leads are for all practical purposes already in parallel anyway. Perhaps somebody makes “unpowered USB hub” you could use as sort of bridge / splice gizmo on each end.
    – Jan Hus
    Aug 15, 2018 at 3:01
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    The first paragraph is also wrong. Having to ports which are limited to 500mA each in parallel could supply 1000mA together.
    – RalfFriedl
    Aug 15, 2018 at 6:18
  • Comments are not for extended discussion; this conversation has been moved to chat.
    – goldilocks ♦
    Aug 15, 2018 at 14:41

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