Comment by deepsun
6 hours ago
Is it also possible to power a laptop through those adapters? PoE++ can deliver up to 100W of power, more than enough for most laptops.
6 hours ago
Is it also possible to power a laptop through those adapters? PoE++ can deliver up to 100W of power, more than enough for most laptops.
Theoretically yes, practically that hasn't been built yet. I've only seen it for 2.5Gbase-T, and only for 802.3bt Type 3 (51W).
If anyone's aware of something better, I'd be interested too :)
(Then again I wouldn't voluntarily use 5Gb-T or 10Gb-T anyway, and ≈50W is enough for most use cases.)
[ed.: https://www.aliexpress.us/item/3256807960919319.html ("2.5GPD2CBT-20V" variant) - actually 2.5G not 1G as I wrote initially]
Eh.
A lot of laptops won't accept less than 60w
My work laptop won't accept less than 90w (A modern HP, i7 155h with a random low end GPU)
At first everyone at the office just assumed that the USB C wasn't able to charge the pc
I gotta say, I love my macbooks. Every Apple laptop I've owned that has USB-C ports will happily charge itself from a 5V/1.5A wall charger (albeit extremely slowly).
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They probably require higher voltages but I havent seen one myself. I usually just charge y laptop with my phone charger, what is it, 18 watts? Don't care, charges my laptop and the phone that is plugged into it overnight. Why charge at faster speeds when there is no need to
Laptop charges fine regular 5V as well.
My Thinkpad T490 will happily take any power provided voltage is high enough (15V+).
Great. So we got EU laws to mandate USB-C chargers and then get manufacturers that flaunt the spirit of the law by rejecting lower wattages.
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A Mac mini at home used 4.64w averaged over the last 30 days. Even under load it just sips power.
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The issue might not be the wattage bit rather the minimum voltage. (Some?) Macs seems to charge at 15v already, most laptops need 20v
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Most laptops will take 45W. There might be some workstations that don't, but even gaming stuff with 5080s will charge on 45W.
Somewhat, there are a few expensive "PoE to Data + Power" adapters out there
https://www.procetpoe.com/poe-usb-converter/ (some of these are power-only)
The idea of a POE Mac mini makes me happy. It would be a nice way of power cycling it from the switch, tidier than the smart plug I have.
https://hackaday.com/2023/08/14/adding-power-over-ethernet-s...
It's undoubtably a cool solution, but in why do you need to remotely do a hard power cycle? Won't just SSHing in and rebooting be enough?
And when ssh is down because you OOMd or something else?
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PoE Texas sells the most compatible adapters for this use.
https://shop.poetexas.com/products/gbt-usbc-pd-usbc?variant=...
65W 802.3bt and gigabit Ethernet out on the same PD cable.
Also a crude fixed hub for data and a keyboard and mouse for docking laptops:
https://shop.poetexas.com/products/bt-usbc-a-pd?variant=3938...
I can’t find what you want, but you can buy PoE splitters. PoE in, ethernet and power out.
Surely a matter of time until someone does this…
We used PoE hats for a bunch of Raspberry Pis once. It’s definitely a great idea.
I found a 5gbe one that claimed 60W, will power a phone but not the low power laptop I've got here. It probably isn't far off.
I think class 4 tops out at about 71W delivered to the powered device, albeit 90W at the switch port.
Might be a struggle I suspect!
With 802.3bt type 4 (71W delivered, 90W consumed), absolutely achievable with the proper electronics, but would you trust a no-name, fly-by-night NIC to not fry your expensive devices? That's the biggest hurdle. Possibly a company like Apple, Anker, or similar megacorp or high-trust startup could pull if off.
Yes, but look up the prices for PoE switches and you might reconsider.
PoE can be cheap, but usually never cheaper than non-poe. But if you have a PoE switch and spare ports, its very nice.
The problem comes when you try to design a large network and need random PoE ports on end devices where you can't home-run a cable back.
I have a Unifi Pro XG 48 PoE and I love it, but I still don't use PoE for everything. The cost of a (non unifi) poe device + the cost of using one of those ports always exceeds a simple power adapter on the other side (if possible).
I think about this a lot.