Video door phone power supply - one instead of two, parameters and distances

Hello
When installing a video intercom, I would like to replace the two power supplies circled in the diagram below with one, which I would place in a mounting box in the basement. I would like to add that the distance from the door opener would then be about 15m, while the distance from the monitor would be about 5m. My question is whether I can at all replace these two with one (if so, what parameters should it have) and whether the voltage drops will not be too high at such distances?

The wiring diagram of the video intercom:

I think a good DC 14V power supply of about 3A would do the job.
Option 2 - a power transformer in the basement around 17V and a bridge with a voltage stabiliser at the end of each branch.

Thanks very much for the hint, and can this bridge with stabilizer be bought or do you have to make something yourself ? Sorry for the question but I am not the strongest in these matters

mario2306 wrote:

Thanks very much for the hint, and can this bridge with stabilizer be bought or do you have to make something yourself ?

Unfortunately yes - own construction, bridge - 2 capacitors - appropriate voltage stabiliser

And would something like the following link get the job done ?

On the schematic, the Manufacturer recommended 2 power supplies (with similar parameters) - and I wouldn't change that!
Video electronics must have a good power supply/stabilisation.
The electric door opener, on the other hand! - is a second electrical circuit and assuming it is in a metal fence - one lightning strike is enough...(so it is better to separate the videophone and electric door strike circuit on separate power supplies)
You may also need to replace the electric door strike with a different voltage (e.g. 24 Vdc)? - replacement of electric door strike and power supply, and the rest of the installation - unchanged.

There are also surges from the abutment.

You're exaggerating the problem a little - a properly done installation shouldn't pose a problem. Many intercoms or video intercoms are built on a single power supply. We know very well that these power supplies will not last too long.
Secondly - one power supply line terminated with a separate stabiliser is also safe. Manufacturers are well aware that each of these power supplies will "die" 2 weeks after the warranty. This begs the question - is it better to do as you please, install the circuit and let heaven do its will, or is it better to subsidise a few pennies and make the installation last for years? The author of the post found a beautiful regulated inverter with a capacity of 2 A. A friend and I used to build various "miracles on a stick" ourselves and it worked brilliantly for us - not only that - it was indestructible.