Gravity: Water Flow Sensor (1/2") For Arduino

This Gravity Water Flow Sensor brings flow-rate measurement and water-volume tracking to irrigation, appliance monitoring, and DIY metering projects. Based on the YF-S201 design, this 1/2-inch sensor combines a plastic valve body, a magnetic flow rotor, and a Hall-effect sensor to measure liquid flowing through a pipe. The 1–30L/min range suits projects that need more information than a simple water-presence reading. A pulse output lets a microcontroller calculate flow rate and accumulated volume, while the Gravity interface supports convenient connection to an Arduino IO Expansion Shield.

Measure Flow Rate and Total Water Volume

Each liter passing through this water flow sensor generates 450 pulses, turning water movement into countable data. Counting pulses over a measured time interval provides flow rate, while accumulating pulses provides total volume. This Hall-effect measurement approach supports both live flow displays and records of water delivered during a watering cycle. The specified ±5% accuracy applies within 2–30L/min, helping distinguish the supported measurement range from the range covered by the accuracy specification.

Gravity Connection for Arduino Projects

The Gravity interface simplifies connecting this water flow sensor to the Arduino IO Expansion Shield, bringing pipe-flow data into an existing controller project. Rather than requiring an analog voltage-to-flow conversion, the pulse output can be counted through a suitable digital input. This interface makes the sensor a practical addition to irrigation controllers and water-use displays. A separate valve or pump, together with suitable control hardware, can act on the measured flow when automatic water regulation is required.