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257 points voxadam | 1 comments | | HN request time: 0s | source
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skopje ◴[] No.45663732[source]
PoE is awesome. My custom home security system is all CCTV PoE with a gstreamer backend running on four-core fanless linux box. Way to go. Complete control. No batteries, no wares spying on me, no personal data getting scraped by big guys. (Cloud connectivity sucks because I have segmented mp4s and jogging through them hurts but I only care for events after they happen, not while they happen.)
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dheera ◴[] No.45665099[source]
Except when it isn't awesome. There are multiple PoE standards. Passive PoE, active PoE, PoE+, PoE++, PoE+++, 802.11af, 802.11at, 802.foo, blah blah.

If they had just stuck with 12VDC and buildings had 12VDC wall sockets everywhere, everything would have been fantastic.

I also had a PoE HAT for a RPi that smoked it. Never doing PoE again. 48V and 3.3V electronics probably don't belong within 10cm of each other.

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eqvinox ◴[] No.45665487[source]
> There are multiple PoE standards.

No, there aren't, not in the way you imply. There is the IEEE 802 PoE standards, which are all compatible (save for not enough power), and designed to carefully negotiate and especially never break non-PoE devices. And there is bullshit (sorry) like "Passive PoE" that is ironically an active violation of the IEEE specs, can break pretty much anything, and you shouldn't buy so the likes of Ubiquiti and Mikrotik finally get the wallet vote and stop f*cking doing. Unfortunately, the proper PoE PD logic is a few dollars of extra expense.

Yes, there is a slightly higher risk of killing devices due to faults in the PoE supply logic. I have the official PoE HAT for a RPi 4. I have to say it is somewhat poorly designed due to space constraints; the isolation between 48V and 3.3V should be better. I'm not even sure the RPi PoE HAT is spec compliant.

But I don't think you can/should blame this on PoE.

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yread ◴[] No.45665551[source]
I have a ubiquiti 30w poe+ injector that somehow doesnt provide enough power for 20W aruba AP. When I plug it in a 120W switch it works unless the cable gets too twisted or something. I vote not awesome
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eqvinox ◴[] No.45665608[source]
Don't buy Ubiquiti. Personally speaking, anyone doing passive PoE (even if only on other device series you're not looking at) is automatically on my shitlist.

I'm not surprised they can f* up a basic PoE injector. The reason for doing passive PoE is saving a few bucks, on the back of safety and compatibility. Of course they would try to pinch hard on the PoE injector too.

Oh and I'd say they (together with Mikrotik) are responsible for 90% of the bad rep PoE gets. The IEEE 802 stuff really just works. And I say that having been part of rolling out 15000 people conference deployments with several hundred wifi APs in the span of a few days. The only real problem is broken cables, but the Ethernet link commonly fails before PoE is impacted.

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1. radicality ◴[] No.45671901{4}[source]
Fwiw, I’ve had a few different PoE switches from Ubiquity and at least so far haven’t had any problems with the switches. My current one is the 48 Pro-Max etherlighting , and I have around fifteen PoE devices and it’s pretty much plug and play always.

I did have issues with some of their other products - eg an old CloudKey gen1 that I had remotely in my parents place that I think ran out of space to the point it can’t update itself and can’t compact some old mongodb.