Introduction

The Water Flow sensor measures the rate of a liquid flowing through it. The YF-S401 water flow sensor consists of a plastic valve body, flow rotor and hall effect sensor. It is usually used at the inlet end to detect the amount of flow. When liquid flows through the sensor, a magnetic rotor will rotate and the rate of rotation will vary with the rate of flow. The hall effect sensor will then output a pulse width signal. Connect it to a microcontroller and you can monitor multiple devices such as your coffee maker, sprinkler or anything else, and control the water flow rate to suit your needs!

• A 6 mm hose is recommended
• Avoid unit contact with corrosive chemicals
• The unit must be installed vertically, tilted no more than 5 degrees
• Liquid temperature should be less than 120 C to avoid damage to unit

Specification

• Inner Diameter: 4 mm
• Outside diameter: 7 mm
• Proof Water Pressure: <0.8 MPa
• Water Flow Range: 0.3-6 L/min
• Voltage Range: 5~12 V
• Operating Current: 15 mA (DC 5V)
• Insulation Resistance: >100 MΩ
• Accuracy: ±5% (0.3-3L/min)
• The Output Pulse High Level: >4.5 VDC (DC input voltage 5 V)
• The Output Pulse Low Level: <0.5 VDC (DC input voltage 5 V)
• Output Pulse Duty Ratio: 50% ± 10%
• Water-flow Formula: 1L = 5880 square waves
• Working Humidity Range: 35% ~ 90% RH (no frost)
• Dimension: 58*35*26 mm/2.28*1.37*1.02 inches
• Weight: 30g

Board Overview

Pulse Signal

Tutorial

In this Tutorial, we'll measure liquid flow using this sensor.

Requirements

• Hardware

  • DFRduino UNO R3
  • Water flow sensor
  • Jumper Wires

• Software

  • Arduino IDE, Click to Download Arduino IDE from Arduino®

Connection Diagram

Sample Code

/***************************************************
 This example reads Water flow sensor Sensor.

 Created 2016-3-13
 By berinie Chen <bernie.chen@dfrobot.com>

 GNU Lesser General Public License.
 See <http://www.gnu.org/licenses/> for details.
 All above must be included in any redistribution
 ****************************************************/

/***********Notice and Trouble shooting***************
 1.Connection and Diagram can be found here  https://www.dfrobot.com/wiki/index.php?title=Water_Flow_Sensor_-_1/8%22_SKU:_SEN0216
 2.This code is tested on Arduino Uno.
 ****************************************************/
volatile double waterFlow;
void setup() {
  Serial.begin(9600);  //baudrate
  waterFlow = 0;
  attachInterrupt(0, pulse, RISING);  //DIGITAL Pin 2: Interrupt 0
}
void loop() {
  Serial.print("waterFlow:");
  Serial.print(waterFlow);
  Serial.println("   L");
  delay(500);
}

void pulse()   //measure the quantity of square wave
{
  waterFlow += 1.0 / 5880.0;
}

FAQ

More

CAD File

Shopping from Gravity: Digital Water Flow Sensor For Arduino - 1/8" or DFRobot Distributor.