Power over ethernet

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Power over ethernet
My cable guy at work decided to have a little fun with me. He came into my office and plopped this down on my desk asking for production approval (with a pretty good straight face too!)
TheUltimateMacUser's picture
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Ha!

LOL. that's funny. Just be carefull, don't leave that laying around or it may fall into the hands of someone who does not know better!

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It's not actually connected.

It's not actually connected.

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Heh.

There's one of these floating around the network operations bullpen at work. I'm hoping no one shows it to the VP of Operations. He might believe it's real and pitch a fit about having wasting money on those PoE switches for the phone system.

--Peace

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what if

If it was wired, how would it be wired, and what would happen if you tried to use it, plugged it into a mobo or big switch?

It'd be neat if the IP over Power hardware was as simple as that (kind of slick). I realize IPoP (?)has its limitations, but maybe its possible to squeeze a whole other low-bandwidth internet in the existing power grid. Maybe... its already there.

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nope

your networking gear isn't designed to handle 120v. You would defiantly kill the router/switch, and potentially damage stuff hooked up to it. Feeding 120v into the ethernet port on your standard networking device is a good way to release the magic smoke.

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PoE is low voltage DC current

PoE is low voltage DC current, not high voltage AC. It uses the unused pins and lines in Cat-5, so all that's required is a connection converter at both ends, which is easily home-brewed. In _theory_ there should be no problems plugging a cable carrying PoE into a standard switch/router.

In practise, someone may have wired up the PoE cable/converter wrong, or the port on the device may be non-standard or faulty, in which case you risk flaky behaviour at best, and smoke ejection at worst. I doubt that Cat-5 could handle more than a few milliamps/ a few milliseconds at 120V before melting, but in that time it could easily kill anything mis-connected at the other end.

Powerline networking is a different beast altogether. You're pumping packets into the building's mains wiring. There are no spare wires, so the data has to be modulated into the mains AC waveform. That requires a whole buncha different electronics, including protection, and is not recommended for homebrew at all nosiree.

It's a nice joke piece from a bored techie.

Jon
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Microsft discontinued a perso

Microsft discontinued a personal powerline network system a few years ago. I forget the name, but it needed a special card/box for each machine. I'm pretty sure it was decentralized so I don't know how useful it was over basic home filesharing and maybe sharing a machines internet connection to the network.

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Re: PoE is low voltage DC current

DrBunsen wrote:
PoE is low voltage DC current, not high voltage AC.

You yanks are uselesss. 110V isn't serious. You wanna do 220/240V over Cat-5, like we do in Europe. That'll teach the kids not to stick their fingers in the 'phone socket.

[Please assure me that PoE is used discriminately in the US. Otherwise I fear that I would have been one of the inquisative kids who sampled it.]

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How much current can you get

How much current can you get away with?

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Well... thats a tough one.

Well... thats a tough one.

Technically it isn't the voltage that kills you, it's the amperage. In theory, one could take a 10,000v shock and although it would hurt like the dickens, you would walk away, assuming the amperage was really low. However, a 10v source, for example, with a high enough amperage will easily kill you.

Jon
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I've been bitten by 110v enou

I've been bitten by 110v enough times, and I've been tazered. I've had other shocks too. Really, I think the 110v was worse than the tazer. I don't know the voltage of the tazer, but a bunch of us were playing with it and I ended up with a shock to the back of the thigh. It sure didn't have a lasting sting/throb like getting a 110v to the fingers.

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