I'm using a photocell for one of my hobby projects. The photocell is a simple resistive sensor, i.e. it generates a resistance that depends on light intensity.
The sensor is connected directly to 5V, and through a 10k resistor to ground. The signal fed to the uC is the voltage across the 10k resistor.
When mounting my circuit for actual use, I will need to place the sensor 10-20 ft away from the circuit.
Is the direct connection I am currently using good enough, or should I look into Kelvin sensing or some other multi-wire hookup ?
What kind of wire should I use ?
Should I add any circuit protection, in addition to the 100nF decoupling cap on the uC input ?
I'm interested in what's best/good enough in this particular case, as well as the more general case of any resistive sensor at various cable lengths.