YF-S201 12mm Water Flow Sensor

The Water flow sensor can be used to measure the flow of liquids, i.e. the consumption of liquids in industrial or domestic usage. For example you can make a robotic cocktail dispensing machine, and can use this sensors to accurately measure components like Soda, Water, etc. Water flow sensor consists of a plastic valve body, a water rotor, and a hall effect sensor. When water flows through the rotor, rotor rolls. Its speed changes with different rate of flow. The hall effect sensor outputs the corresponding pulse Signal.

I believe using this should be simple, you just need to connect to Arduino interrupt pin 2, and can measure the number of PWM pulse/interrupt per unit of time. The water flow would be directly proportional to the number of measured pulses.

Connection details:

• Red wire is +5V.
• Black wire is GND.
• White wire is PWM signal output.

Description:

• Lowest rated working voltage: DC4.5 5V-24V.
• Maximum operating current: 15 mA (DC: 5V).
• Working voltage range: DC 5~18V.
• Load capacity: ≤ 10 mA (DC 5V).
• Temperature: ≤ 80 ℃.
• Operating humidity range: 35%~90%RH (no frost).
• Allowed pressure: pressure 1.75Mpa.
• Temperature: -25~+80 °C.
• External threads: 1/2″ or 12 mm.