The Water Flow Sensor (YF-S401) is a compact and efficient sensor designed to measure the rate of liquid flow in a system. It uses a rotor mechanism with embedded Hall-effect sensor to detect water movement and convert it into a digital pulse signal. By counting the frequency of the pulses, the system can accurately determine the flow rate in liters per minute. Its small size, high sensitivity, and stable performance make it widely suitable for home appliances, water dispensers, coffee machines, irrigation systems, and industrial control projects.
The YF-S401 is built with durable materials that resist water damage, ensuring a long operational life. It is lightweight, easy to install, and compatible with popular microcontrollers such as Arduino, ESP32, and Raspberry Pi. With its high accuracy and reliability, it is an excellent choice for projects requiring real-time monitoring of water usage or flow rate.
How It Works
The YF-S401 consists of a plastic valve body, a water rotor, and a Hall-effect sensor. When water flows through the sensor, it rotates the internal rotor. The Hall sensor detects this movement and outputs a series of electrical pulses. Each pulse corresponds to a fixed volume of water. By measuring the frequency of these pulses, the microcontroller can calculate both the instantaneous flow rate and the total volume of water that has passed through the sensor. This makes the YF-S401 ideal for precise liquid control and monitoring applications.
Key Features
Compact and lightweight design
Hall-effect sensor for accurate measurement
Provides digital pulse output signal
Wide measuring range suitable for home and industrial use
Easy integration with Arduino, ESP32, and Raspberry Pi
Low power consumption and stable performance
Durable plastic housing for long-term reliability
Specifications
| Parameter | Value |
|---|---|
| Model | YF-S401 |
| Operating Voltage | DC 5V – 18V |
| Max Current | 15 mA at 5V |
| Flow Range | 1 – 30 L/min |
| Pressure Range | ≤ 1.75 MPa |
| Output Type | Digital pulse signal |
| Connector Size | G1/2 inch thread |
| Accuracy | ±10% |
| Material | Durable plastic body |
Pin Configuration
| Pin | Name | Description |
|---|---|---|
| 1 | Red | VCC (5V – 18V) – |
| 2 | Black | GND (Ground) |
| 3 | Yellow | Pulse Output Signal |
Applications
Water dispensers and coffee machines
Domestic water flow measurement
Irrigation and agricultural automation
Industrial liquid flow monitoring
Smart home water usage tracking
Scientific and research experiments
