water flow sensor yfs401

the water flow sensor yfs401 is an electronic device used to measure the flow rate of water or other clean liquids through a pipe, commonly used in applications such as water dispensers, irrigation systems, industrial equipment, and diy electronics projects. it works using a hall effect sensor and a small internal rotor or paddle wheel that spins when water flows through the sensor body. as the rotor spins, it generates electrical pulses, and the frequency of these pulses is directly proportional to the flow rate of the water. the sensor typically has three wires: red for power supply, black for ground, and yellow for pulse signal output, and it usually operates at 5 volts dc. by counting the pulses over a fixed period of time, a microcontroller such as an arduino can calculate the flow rate in liters per minute and the total volume of water that has passed through the sensor. the yfs401 is valued for being low cost, easy to install, and simple to interface, although it requires calibration for accurate measurements and is best suited for low to medium pressure and temperature conditions.