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Hacker mods an M1 Mac mini to receive power over Ethernet instead of AC

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Re: Hacker mods an M1 Mac mini to receive power over Ethernet instead of AC

#13
We powered the Mac Mini M1 using 12V DC, bypassing the built-in AC power adapter, and used it for some quadruped robot experiments. Some details on the connector are here: https://www.ifixit.com/Answers/View/574827/What+PSU+connecto... (that article mentions Mac Mini 2018 but the connector/pinout still works fine for Mac Mini M1)

Re: Hacker mods an M1 Mac mini to receive power over Ethernet instead of AC

#16
This seems to simply ignore the max continuous power rating of 150W. The mini can output 15W on each thunderbolt port and another 15W on its two USB ports, which is already nearly the limit of 51W assured to each PoE++ endpoint, not even counting the mini's own requirements.

Re: Hacker mods an M1 Mac mini to receive power over Ethernet instead of AC

#18

Having inadvertently plugged a 24v passive PoE live connection into an old 2012 Mac Mini and immediately frying it, this is welcome news!

I thought most modern devices had isolation!

Indeed, surprising.

From IEEE 802.3 (revision 2012), section "32.6 PMA electrical specifications":

> The PHY shall provide electrical isolation between the DTE or repeater circuits, including frame ground and all MDI leads.

> This electrical separation shall withstand at least one of the following electrical strength tests: > [...]

> b) 2250 Vdc for 60 s, [...]

Non-compliant Ethernet PHY?

Re: Hacker mods an M1 Mac mini to receive power over Ethernet instead of AC

#19

" the M1 Mac mini was the perfect hardware to test out PoE, as on idle, the device only consumes 6W. When some load is applied to the internals, that power draw can go up to 40W. After some thorough research, we found out that the maximum throughput of Power over Ethernet was 15.4W " They'll have to bump it up to 802.3bt (Poe ++) which can support 60W. Cool Project though, I've been wanting to mod my Mac Mini m1 to r…

What's the goal of having a MacMini running off an external battery? I mean, it seems less cost effective than just getting a MB Air and not using the screen...

Re: Hacker mods an M1 Mac mini to receive power over Ethernet instead of AC

#20
post #19

" the M1 Mac mini was the perfect hardware to test out PoE, as on idle, the device only consumes 6W. When some load is applied to the internals, that power draw can go up to 40W. After some thorough research, we found out that the maximum throughput of Power over Ethernet was 15.4W " They'll have to bump it up to 802.3bt (Poe ++) which can support 60W. Cool Project though, I've been wanting to mod my Mac Mini m1 to r…

What's the goal of having a MacMini running off an external battery? I mean, it seems less cost effective than just getting a MB Air and not using the screen...

The goal of most of these projects are usually to demonstrate that they're possible. Actual use cases are left as an exercise for the reader.
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