I am trying to hook up and read from numerous sensors. (Same 50 sensors)
Whether the sensor is weight sensor, or ultrasonic sensor.
I have a question on how it should be connected where wirings could be minimized and # of arduino used to be minimized?
It seems that arduino is only able to support up to ~9 sensors at a time.
Therefore, I have also considered using 1 master arduino and using multiple slave arduino's?
FYI : All 50 sensor data does not have to be fed to arduino simultaneously. It can be done in series.
I have 50 devices around my house (sensors, lights and switches) that communicate using MQTT over WiFi. Almost all of them are on ESP8266 boards or products, like the Sonoff's.
You don't say which sensors or which protocol they use or what distances you are talking about, but if you use I2C you can put several on one board. (I2C is not designed for long wire lengths)
I would put each sensor on it's own ESP board. You can get the ESP01 for $1 in quantity, or the Wemos D1 Mini for $5.