Two 250m PoE IP cameras over one cable?

Question

Electronics

Good afternoon.

The task is to stretch 4 ip cameras at a distance of 250m.
There is a PoE switch for 4 ports. In Extended mode, 250 m is quite realistic, albeit at 10 Mbps.
Question: Is it possible to connect 2 cameras on one cable? To pull not 4 cables, but at least 2.
As far as I know, PoE power through 4/5/7/8 cores produces 48v.
If I remove the 4 + 7 power wires and feed them to one camera, and 5 + 8 to the second, will it work?
Or do I need some kind of 48->12v converter.

Answer 1

Modern PoE switches with Ae / Af mode allow you to power two cameras from one eight-wire twisted pair - I did this for several objects, though I never risk such a long length.
You just uncover the twisted pair cable into two 4 cores, crimp it and everything should work. But I did this only when the client had wires in the cottages and it was not possible to run new ones ..
I still advise you not to save and throw a whole 8 -wire wire for each camera, because if in the event of failure of at least one of the cores, the camera will immediately "fall off" and this is an unreliable option ..
And what is written that it will work under 250 m, I advise you to check it all the same before mounting at such a length .. I would not risk it ..
Just in case, there are such things - MikroTik GPeR ..
https://mikrotik.ru/katalog/katalog/components/int...

Answer 2

Don't worry about anything.
Pull one wire, put Mikrotik RouterBoard 260GSP on the other end, power it via POE and it transmits the same POE to the following devices.
It is cheaper, easier, and most importantly more reliable than your bunch of whirlpools, especially 2 cameras each.
And by the way: if you have one camera, by some prayers, and can withstand 250m, then 2 are already unlikely, because. there will be much more interference and interference and there is nothing to shield them with