Increase power available to usb port and SoC with higher amperage ac adapter? Also, will this run on 12v (10 to 14v) DC power from a car

Hardware Questions and Recommendations
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I am working to streamline my home network after moving my homelab into a datacentrr colo as i prepare to live the vanlife. So far im absolutely in love with the e8450 i bought because its completely slamming the compressed network load i used to serve from several VMs, now running as services on openwrt, AND is working great with the software tap from easy tether.

The issue i have is that when i move into my overlanding truck later this year i want to have flexibility on network connections, so it will failover between easytether cell as a last resort, wifi wwan if needed and available, and starlink if theres a clear skyview.

The problem i encountered is that with a cellphone charging off the usb port and a wifi usb adapter, it seems to be robbing power from the SoC. So my temporary solution is just to use a self powered usb hub. Im aware its only 480mbps usb2, but my needs are just connectivity, not speed. 5mbps is ok

Im no electrical engineer, but if i connect a 12v adapter with a higher amerage output, will that fry the router or provide the power needed for the additional usb load?
Also, if i connect this router to 12v battery output really 10v to 14v in practice with a 6amp or equiv fuse inline, will this likely work properly without converting dc to ac to dc?

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It won't fry it, as a circuit only uses the amps it needs. That still doesn't mean it'll deliver the power to the port.

  • Feel free to safely test.
  • Do not use a different voltage

Not sure of your question, but do not attempt to use AC power on a DC circuit, period.

If you mean you're using DC power - like from a 12v lead acid battery and not a wall wart (i.e. DC-to-AC transformer), yes the 12v battery will work.

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This is the solution I would have recommended. You are already on top of this! It's not elegant, but assuming you're using a hub with enough capacity, it means you can ensure that both of your USB devices have enough current and it also ensures that you will not brown-out the router itself.

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Be aware that the alternator does not stop at 12.0V, nominally it's supposed to deliver 13.8V - and in practice you may see up to 16V. Likewise car electrics must be resilient to intermittent overcurrent peaks up to 190VAC and 300VAC (e.g. from the spark plugs), do not expect your router to survive either (especially not long term).

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The house side of my vanlife truck will be powered by a DC/DC charger, so there will be some regulation on the power output since it will be flowing from the lithium powerbank and not directly from the alternator.

@psherman
Agreed it's not elegant, but I'm also trying to cut down on dongle and adapters, so I'm hoping more current into the router allows for 1 power source. We will see.

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This has a 12v dc input from the regulated ac supply supplied with it.

The usb port is supplied with 5v dc from a regulator inside the router. These are designed usually to supply one usb device such as a 4g dongle.

Putting a beefier supply will usually do nothing unless the supplied one is very under rated for the job or possibly faulty.

You can buy buck regulators that are very cheap and efficient and will reduce input dc to 12 volts (or anything else you want). Ideal for the router.

Use a powered usb hub and give it its own buck regulator. (search on Amazon).

Direct connection to a car battery will sooner or later fry something.

Likewise a "12v" LiFePO4 bank will be a little over 14 volts when fully charged so always use a buck regulator there too.
(A buck reg is a "switched power supply" and is very efficient)
I know all this because of lots of "off grid" experience and been where you are now but years ago....

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