We've heard about multi-sensor ESPHome projects, like a presence sensor using PIR and mmWave Radar, also installing lux meters, temperature/humidity, etc. The GPIO pins are there, so why not?
I'm curious to hear if anyone has tried running a sort of multi-zone system of different sensors. That is, rather than colocate all of the sensor elements in the same housing, mount the sensors in different locations or rooms, connected to the project board over a longer cable run, like maybe old, disused CAT5, CAT3 or CAT1?
I had an idea where I might make a network of temp/humidity sensors. I have a discarded spool of CAT3 UTP cable. It'd be easy for me to pick a central spot in my home for a hub, and run CAT3 to several rooms through a convenient crawlspace I wonder if i could extend VCC, GND and digital I/O pins to sensors in those other rooms over those hypothetical CAT3 runs? Maybe use a level shifter and common 5V & GND rails off a power cube? I can see analog sensors being an issue because you'd need to figure the voltage drop over the distance, maybe.
It could even use RJ11 or RJ45 terminals in printed housings at each end to keep things neat.
Has anyone tried this? How'd it work out?