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Comment by 0xbadcafebee | Hacker News Reader

I would be so paranoid putting a fanless cheapo PoE switch with no certifications anywhere. Is it really worth a fire? What would your liability be like?

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Same. I cannot imagine who buys these things. You have business-class problems like high PoE current on the same wire as > 1GE traffic, but you're buying no-name, no-support whitebox gear? It just doesn't make any sense.

They sell a non-PoE version.

What kind of support do you think you're going to get with cheap unmanaged switches? We couldn't get meaningful support from one of the big name vendors with their top of the line routers with millions of dollars spent on hardware purchases and support contracts.

You're not really selling the idea of spending more on the big name there. I mean, if the big name is Cisco, then at least the CLI commands come back to my fingers like playing an old piano song, and there's likely to be some documentation from them or a rando's blog, but this is an unmanaged switch - there's nothing to configure.

That said, I'd probably look at TP-Link products; I suppose you could call them the name brand of cheap network gear.

Yep, I got the TP-Link TL-SG1008D recommended by a network guy who works at Eero. $20 for 8 ports, unmanaged, works fine. Not 2.5GbE though, just gigabit.

Ubiquiti for all their faults has a neat 5 port, PoE powered semi-managed switch [0] for 30$ - if you’re looking just at gigabit.

[0] - https://store.ui.com/collections/unifi-network-switching/pro...

Yeah, that was my point :-)

2.5 Gb is becoming the new 1 Gb. 10 Gb networking gear is still often a significant premium over 1 Gb gear but 2.5 Gb is approaching the point where a smart future proofing move would be to avoid buy 1 gig networking gear going forward even if you don’t have a use for more than 1 Gb network speeds right now.

Then it’s a question of why is someone looking for a small, inexpensive PoE switch and PoE cameras are the most likely use I can think of.

My understanding is that PoE is typically 48V and 10g Ethernet is something under 4V.

I'm not up on the latest NFPA codes, but how much of a hazard is 52V? I'm also guessing the quality of the cable is a factor.

You can start a fire with a 24v car battery (and dry tinder, and skill). However, PoE switches only supply power after successful negotiation with the client. You would have to be _seriously_ unlucky to get a cable intact enough to support a connection but damaged enough to start a fire - I don't think I could do it on purpose, even if I had a few days and a stack of spare cables to try.

I'd be more concerned about the power supply (between the wall and the router) than the 48V lines. Would definitely want to be sure that was good quality.

Or a 9 volt some steel wool and not much skill

I feel like that's cheating; steel wool will burn if you so much as look at it funny.

The normal way to do this is to get a dodgy CCA cable with insulation that is not riser rated, and run a bundle of them together into a wall.

One might also consider the quality of the power supply itself, and how much of a fire risk it is.

Here is an (unrelated) PoE injector catching fire: https://community.ui.com/questions/Litebeam-5ac-gen2-poe-ada...

It's a different type of device, but my point here is about mains voltages.

IMO it’s less about the voltage and more about the wattage. A modern PoE spec supporting wattages ~100W is more than enough to start a fire. Currently there is a gap in the electric code (NFPA70) as it doesn’t really address this risk in the (vague) section on low voltage wiring. But building codes are written in blood. I’m sure it’s just a matter of time till some PoE cable starts a fire and then the code will get amended.

especially with TP-Link switches being roughly the same cost and from Amazon.

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