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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

#41

Post by CameronNemo »

dheera wrote: post #35
ravetcofx wrote: post #6

" 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…

I'm very skeptical of PoE now after 3 PoE adapters killed 3 Raspberry Pis I have. I wouldn't want to risk something more expensive to that shit. At this point I'd rather just have straight up 19V + and - cables bundled together with the Ethernet with some heatshrink around the whole thing to make it look like 1 cable.

You sure you want to blame poe as a whole instead of the RPI hat?

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

#43

Post by haswell »

dheera wrote: post #35
ravetcofx wrote: post #6

" 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…

I'm very skeptical of PoE now after 3 PoE adapters killed 3 Raspberry Pis I have. I wouldn't want to risk something more expensive to that shit. At this point I'd rather just have straight up 19V + and - cables bundled together with the Ethernet with some heatshrink around the whole thing to make it look like 1 cable.

PoE is used extensively in network deployments involving rather expensive hardware.

I understand the instinct to avoid it at this point, but I’m curious what happened in your case because I’ve never experienced issues.

I did work somewhere where someone fried equipment by incorrectly terminating a batch of Ethernet cables thereby sending voltage to the wrong place.

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

#44

Post by Dalewyn »

lapetitejort wrote: post #20
r00fus wrote: post #19

Earlier quoted context omitted.

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.

[flagged]

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

#45

Post by clintonb »

JoeAltmaier wrote: post #42

PoE is a mature technology. Curious that laptops have not been on board.

An electrical outlet or USB-C connection is more readily available to me than an Ethernet port with POE. Laptops aren't onboard because the problem of powering laptops is largely solved. Also...not many laptops have Ethernet ports.

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

#46

Post by contingencies »

JoeAltmaier wrote: post #42

PoE is a mature technology. Curious that laptops have not been on board.

Historic energy consumption is probably higher than classically POE supported.

Also, any length of POE run gets voltage drop, and POE switches and injectors often have tedious modal configuration based upon length of run and are designed with non-standard limitations such as maximum draw limits shared across multiple ports, which in aggregate will cause no end of issues. For verification, ask any experienced CCTV installer. These are exactly the sort of issues that cause users to take products back to their distributors.

So it's a case of "works in theory, PITA in reality, probable support and brand image impact huge, resulting priority zero".

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

#47

Post by tyingq »

r00fus wrote: post #19
ravetcofx wrote: post #6

" 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...

That it happens to be 12 volts DC has some value versus whatever power loss an inverter has for use in a vehicle. Though I'm with you on the relative ease of starting with a laptop instead.

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

#48

Post by JoeAltmaier »

contingencies wrote: post #46
JoeAltmaier wrote: post #42

PoE is a mature technology. Curious that laptops have not been on board.

Historic energy consumption is probably higher than classically POE supported. Also, any length of POE run gets voltage drop, and POE switches and injectors often have tedious modal configuration based upon length of run and are designed with non-standard limitations such as maximum draw limits shared across multiple ports, which in aggregate will cause no end of issues. For verification, ask any experienced CCTV ins…

It's really popular in factories etc, because it reduces cable runs I guess.

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

#49

Post by dheera »

CameronNemo wrote: post #41
dheera wrote: post #35

Earlier quoted context omitted.

I'm very skeptical of PoE now after 3 PoE adapters killed 3 Raspberry Pis I have. I wouldn't want to risk something more expensive to that shit. At this point I'd rather just have straight up 19V + and - cables bundled together with the Ethernet with some heatshrink around the whole thing to make it look like 1 cable.

You sure you want to blame poe as a whole instead of the RPI hat?

Sure it could be the RPi hat, but it just means the standard is so complicated that people don't implement it correctly.

I wouldn't trust the hat or whatever you call it for Mac Mini.

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

#50

Post by contingencies »

JoeAltmaier wrote: post #48
contingencies wrote: post #46

Earlier quoted context omitted.

Historic energy consumption is probably higher than classically POE supported. Also, any length of POE run gets voltage drop, and POE switches and injectors often have tedious modal configuration based upon length of run and are designed with non-standard limitations such as maximum draw limits shared across multiple ports, which in aggregate will cause no end of issues. For verification, ask any experienced CCTV ins…

It's really popular in factories etc, because it reduces cable runs I guess.

That's right, but factories have other problems too: especially EMI due to huge loads being switched, which twisted pairs, shielded twisted pair and ethernet termination magnetics are designed to resist. Also, industrial cable routing can get pretty hairy, this means the ability to round a corner at a relatively tight radius can be important. Using standard ethernet cables for low current DC power keeps these concerns generally within acceptable realms of normality.
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