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Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by dheera on Tuesday August 01, 2023 @06:15PM (#36963945)
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.

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by haswell on Tuesday August 01, 2023 @06:37PM (#36964208)
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:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by bob778 on Wednesday August 02, 2023 @02:08AM (#36967533)
That should only be possible if using non-standard "passive" PoE?

802.3bt has negotiation specifically to prevent faulty cables/devices from being powered.

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by CameronNemo on Tuesday August 01, 2023 @06:33PM (#36964167)
You sure you want to blame poe as a whole instead of the RPI hat?
Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by dheera on Tuesday August 01, 2023 @07:00PM (#36964453)
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:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by wolrah on Tuesday August 01, 2023 @07:55PM (#36964979)
> Sure it could be the RPi hat, but it just means the standard is so complicated that people don't implement it correctly.

Or there are ways to cheap out on a PoE device that may work in some cases but don't fully and properly implement the standard.

The standard is widely used in VoIP phones, wireless access points, security cameras, and all sorts of other networked devices that get installed in places that may not have nearby power outlets or where a single wire solution is beneficial.

Personally I have three Pis that have been on PoE their entire lives and have had no problem, but I used a name brand PoE hat (the Waveshare hat with the OLED display) and am powering them from a mainstream PoE switch. If you're using some random AliExpress hat with janky injectors you get what you pay for.

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

Almost any large commercial building has had hardware running on PoE that costs more than the average Mac Mini for years. Most PTZ cameras for example, high-end directional wireless bridges, even some nicer wireless access points.

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by dheera on Wednesday August 02, 2023 @02:24AM (#36967642)
I mean, one of my hats that fried one of my Pis was a Waveshare hat. This one actually

https://www.amazon.com/gp/product/B0974TK3KD/

PoE operates at a pretty high voltage (almost half of line voltage!) and Waveshare products aren't UL listed.

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by NavinF on Wednesday August 02, 2023 @01:44PM (#36974233)
>PoE operates at a pretty high voltage

No, it operates at ELV (extra-low voltage): https://en.wikipedia.org/wiki/Extra-low_voltage

The whole point of PoE, 48V PD USB-C, and similar tech is that they don't need to be UL listed. PoE is also electronically current limited unlike mains power so you can't pull 200A to start a motor nor can you start fires without a lot of effort. That's assuming you use a real PoE switch that negotiates power levels, not cheap passive injectors.

Anyway that hat has some bad reviews claiming DoA, missing components, and dead Pis. Why not get the official hat? https://www.raspberrypi.com/products/poe-hat/

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by NovemberWhiskey on Wednesday August 02, 2023 @09:53AM (#36970925)
You're dealing with the same manufacturers that won't even bother to include the USB C termination resistors required to make "USB C" charging ports on their devices work with actual USB-compliant PD. You're talking about the kind of part that's so cheap that adding five of them is going to round down below a penny in your BOM. The kind of manufacturer that, if it had a motto, that motto would be "no corner too cheap to cut".
Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by SV_BubbleTime on Tuesday August 01, 2023 @08:34PM (#36965323)
It’s definitely that.

PoE is fine and the issue surely lies on some $5 Chinese rasppi part with little buffering and protection circuitry.

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by wil421 on Tuesday August 01, 2023 @07:04PM (#36964490)
I have 13-15 devices running over PoE at my house and all of them work just fine. Everything from the high end Ubiquiti gear to raspberry 3/4 PoE hats. It’s powered by a Unifi 24 port PoE switch.

The only time I had issues was with a 2 mesh APs and sketchy power at a condo that has minor power outages due to thunderstorms. I brought the devices back home and they work fine, the new device doesn’t have an issue. I was curious if a UPS would’ve smoothed the power blips but the new AP restarts and connects just fine.

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by NavinF on Tuesday August 01, 2023 @07:33PM (#36964778)
PoE switches and devices are widely used in industry. I suspect your 3 PoE adapters are "passive PoE" consumer crap that doesn't meet spec
Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by Alupis on Tuesday August 01, 2023 @08:05PM (#36965062)
What kind of PoE Adapter/Hat did you use?

From memory, and it's been a few years/models... but the GPIO pins, including the 5V input pin bypassed all of the circuit protection fuses and what-not the normal barrel jack had.

It wasn't uncommon for people to roast their RPi with incorrectly done, or poor quality GPIO powering devices.

Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by hnbad on Wednesday August 02, 2023 @02:20AM (#36967619)
This is still true. There are ample warnings to be careful when using the GPIO as input because of this. The hat probably passed on some variance that is supported by actual consumer devices and fried the RasPi because it has no protections.
Re:Mac Mini M1 Mod to Receive Power over Ethernet Instead of... by epcoa on Tuesday August 01, 2023 @09:41PM (#36965892)
Don’t buy eBay junk and blame it on the standard - which is used by tons of high end commercial equipment and is more appropriately a commercial feature - PoE isn’t cheap - if it is that probably explains your poor results.