Power ip camera, 12v over twisted pair?

Question

Cables and wires

It is necessary to connect the ip camera via twisted pair cable 8 wire, 4 wire for data and 4 wire for power. There are no POE switches, as it is expensive. Cable length up to 30 meters maximum, some 10 meters long.
Twisted pair copper 24awg 0.52mm in diameter (it is important to note that this is not a section but a diameter). according to online calculators, already at 22 meters the voltage loss is 18.5%, which will give instead of 12v, 9.8v and the camera will probably not work.
Will the voltage loss decrease if you throw two different wires on + and - and connect them at the ends? Or will the losses on them still be the same?
If the camera supports POE, is it possible to apply more voltage to it? Will the camera itself lower it? Or POE injectors themselves coordinate the voltage with the camera on each port separately?

Answer 1

Will the voltage loss decrease if you throw two different wires on + and - and connect them at the ends?

Of course, according to Ohm's law. The area will double (you can substitute the equivalent diameter multiplied by the root of 2 into the calculator).
In any case, you can take an adjustable power supply and give out, say, 15 V (how much is required, taking into account the losses and the range of the camera).

Answer 2

We connected Hikvision ip cameras with such a scheme for a distance of 30 meters, a power supply of 12 volts 5 amperes, 3 cameras on one unit, they have been working without problems for a year

Answer 3

Just calmly connected and 30 or more meters in this way. Everything is working. There were Hikvision cameras.
Only with us, when twisting 2 wires, the cable began to heat up strongly. They let in 1 contact (through brown veins), the problem disappeared.
You can also use POE injectors or POE adapters. The camera usually does not know how to lower the voltage. Power only 12v.

Answer 4

More practice mate.
Using this technique, you can stretch almost any camera up to 100 meters. Personally, in my experience, all Chinese noname cameras work like clockwork, they also experimented with the HiWatch line of cameras - the same thing works, even though it's a perversion.
There are good power supplies on the NGShop website (yes, you can buy them from yourself for a regular 12v LED strip). Just keep in mind that for such a perversion it is necessary to give 1-2 amperes more, otherwise there will be troubles in operation, and in particular in braking the picture (again, if you pull the winder to the maximum)