Questions about POE

[MrData]

I'm looking to buy 1 or 2 new cameras and I see that POE cameras don't come with any way to inject the P into the E, gotta buy that separately.
When I look at POE injector devices, they're listed at 48v or 24v. The cameras I have now are all standard 12v. Do newer cameras take any voltage and
regulate it down to 12v or are some cameras 24v and some 48v. Ideally I'd like to try using a small 12v sealed battery and a solar charger.
It would also seem that using POE with all the injectors and switches and whatnot is a bunch more expensive than running long power wires from individual wall warts inside the house.
Other than the simplicity of one wire connection, is there a benefit to using POE?
--Thanx

 

[Mike A.]

Yes, standard POE adjusts to meet the power requirements of the device. There are some exceptions which use some non-standard power levels, etc. The 24v that you're seeing likely are some of the latter.

Typically, you'd use a POE switch which provides power to the device and the data connection over the same cable. Not individual injectors plus the usual non-POE network switch (other than maybe in some special circumstances).

Running a bunch of whatever low-power wires all over would be a mess. And you'd still need the data connection so you'd need to run the same cable you'd use for POE anyway.

 

[tigerwillow1]

POE cameras use nominal 48 volts DC combined with the data on the ethernet cable. The camera's separate power input is commonly 12 volts. Offhand, I guess simplicity is the only reason to use POE, but that one benefit is huge. Using a POE switch is the easiest path to take. Besides providing the power they also have overcurrent protection for each individual port. I've looked at the innards of a few cameras and they all convert the POE power to 12 volts for powering the camera. They're of course free to do it any way they want internally.