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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

#161

Post by bogantech »

Cthulhu_ wrote: post #139
forgotusername6 wrote: post #126

Earlier quoted context omitted.

Plenty of domestic applications still require higher voltage (well actually power but I presume you aren't suggesting 12V with high current). Vacuum cleaners, hair dryers, anything portable that produces heat. Building houses with low voltage sockets would be really frustrating for people living there. Is the danger of 230V actually significant in this day and age? I wonder how many fires/injuries are caused by 230V…

Fires and injuries at 230V aren't caused by the voltage, but by improper installation and handling. Don't stick forks in outlets, turn the power off when you're working with it, etc. Also, it's not the voltage that kills you, it's the amperage. With regards to the 12V discussion, there's also AC vs DC to consider; AC will flip voltage 60x a second, making your heart go haywire, whereas DC is a continuous jolt, meanin…

I=V/R

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

#162

Post by smileybarry »

mrweasel wrote: post #117
ancorevard wrote: post #82

Has anyone accomplished powering an Apple TV with PoE?

That's what I want as well. It will/should always have an Ethernet cable attached anyway, but why do I need to run two wires? Apples are a little weird, in that they clearly have no love for cables, yet they refuse to adopt PoE. The AppleTV and HomePods are prime candidates for PoE.

I also wish the HomePod supported wired networking in some constellation. It's powered via USB-C but only uses it for power, whereas you could totally use some USB-C + Ethernet dock. It's not like iOS (which HomePods are kinda based on anyway) doesn't support those.

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

#164

Post by shagie »

bravetraveler wrote: post #152
shagie wrote: post #90

Earlier quoted context omitted.

> ... but batteries are consumables. I like these things to be easy-to-replace! Replaceable, consumable batteries often get thrown out in the trash. ... and can set garbage trucks and recycling centers on fire. https://www.waste360.com/safety/lithium-ion-batteries-are-ca... https://www.dispatch.com/story/news/local/2023/02/09/garbage... https://arstechnica.com/gadgets/2022/12/recycling-firm-fined... https://gothamist…

I wish I knew a good answer - this is an excellent concern. I'm skeptical of recyclers/waste centers, but that's what I've got.

Having things that are have special handling for disposal not be as user serviceable is one solution... but that goes against the replaceable battery.

The AA lithium ion batteries getting tossed into the trash and setting garbage trucks on fire are problematic enough. The energy capacity of a cell phone is quite a bit more and correspondingly more spectacular in the combustion.

From iFixit:

https://www.ifixit.com/News/69041/how-batteries-can-catch-fi...

https://www.ifixit.com/News/34034/lithium-ion-batteries-are-...

> USA Today reports that 65 percent of fires at waste facilities in California were started by lithium-ion batteries. In a 2018 survey of 21 waste facilities across California, 86 percent reported a fire at their facility in the last two years, according to the California Products Stewardship Council (CPSC). Of those fires, 56 percent were attributed to batteries, with the remainder attributed to “traditional hazards of combustibles.” In other words, batteries are causing more fires than the oils, fuels, and other hazardous materials of waste management—combined.

> And that’s only the fires actually reported.

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

#166

Post by xp84 »

shagie wrote: post #90
bravetraveler wrote: post #79

Earlier quoted context omitted.

Thank you for taking the time to follow up! Definitely a bit paranoid - even if I'd prefer to call it robust :) I've had very bad luck in this regard... but haven't honestly used a laptop in probably a decade. I was pleasantly surprised to see my latest (dust-collecting) Lenovo will stop somewhere around 80%! Point being, sure - there are safety things... but batteries are consumables. I like these things to be easy-…

> ... but batteries are consumables. I like these things to be easy-to-replace! Replaceable, consumable batteries often get thrown out in the trash. ... and can set garbage trucks and recycling centers on fire. https://www.waste360.com/safety/lithium-ion-batteries-are-ca... https://www.dispatch.com/story/news/local/2023/02/09/garbage... https://arstechnica.com/gadgets/2022/12/recycling-firm-fined... https://gothamist…

Respectfully, today people just chuck the entire phone/laptop in the bin. I don’t think making the battery module removable changes the outcome one bit, except that it would allow a tremendous amount more life out of these devices, reducing all the other (non-battery) waste streams and reducing the environmentally costly manufacture of new devices…. which is the reason why the shareholders love the current strategy and why all electronic manufacturers are moving the same way. Why allow users to get 3 more years of life from their laptop when you could convince them it’s e-waste after 3 because of a $15 battery?

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

#167

Post by NavinF »

monocasa wrote: post #52
mmastrac wrote: post #14

Earlier quoted context omitted.

I thought most modern devices had isolation!

It should be that all devices have isolation. Ethernet is capacitively coupled which keeps you from having to coordinate your power/ground between devices. PoE is the recognition that if the DC levels don't matter because of that required isolation, we might as well not isolate in a power stage before the magnetics and deliver some DC power.

> Ethernet is capacitively coupled

It's usually magnetically coupled. I've only seen capacitive coupling when both devices are on the same PCB

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

#168

Post by xp84 »

NavinF wrote: post #105
dylan604 wrote: post #62

Earlier quoted context omitted.

how does that work if the case is never opened?

You can connect multiple switches in series. Eg one could be a reed switch that detects whether the PC is within 1mm of a tiny magnet in the floor.

This is a good idea! Kind of makes me wish I was a drug kingpin with a PC full of secrets so that I could justify trying that. Sadly I would just end up with a kid rebooting the PC by bumping into it :D

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

#169

Post by xp84 »

rfgmendoza wrote: post #28
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 would actually like being able to power my mac mini with just a usb-c dock like a macbook

I have been thinking it would be cool to just salvage a functional MacBook Air motherboard from a “broken” device. install that in a small case, 3D print an IO shield, and you have what you’re looking for!

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

#170

Post by tnecniv »

SkeuomorphicBee wrote: post #142
Cthulhu_ wrote: post #139

Earlier quoted context omitted.

Fires and injuries at 230V aren't caused by the voltage, but by improper installation and handling. Don't stick forks in outlets, turn the power off when you're working with it, etc. Also, it's not the voltage that kills you, it's the amperage. With regards to the 12V discussion, there's also AC vs DC to consider; AC will flip voltage 60x a second, making your heart go haywire, whereas DC is a continuous jolt, meanin…

> Also, it's not the voltage that kills you, it's the amperage. A bit off-topic but I never liked that saying, it is kind-of-right but also soo wrong in so many levels. Amperage is not a thing that happens on its own, it is always a result of voltage, voltage is the driving force, so it is the voltage that actively kills you, by forcing amperage through your internals. When the killing happens the voltage is the real…

My hypothesis has been that the saying is due to how we generally think about power supplies. The voltage is a fixed quantity but the current fluctuates based on what the circuit asks for and what the power supply can give you. Something could be rated at 100V, but if the supply can’t deliver any significant amps it doesn’t matter much
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