Reading Water Flow Rate from a flow meter.

https://forum.arduino.cc/t/reading-water-flow-rate-from-a-flow-meter/8612

 

 

 

This is part of a project I have been working on and I thought I would share it here . The flow meter I am using is the Water Flow Sensor found in the Seeed Studio Depo. It uses a simple rotating wheel that pulses a hall effect sensor. By reading these pulses and implementing a little math, we can read the liquids flow rate accurate to within 3%. The threads are simple G1/2 so finding barbed ends will not be that hard. I found some at lows for $1.89 each.

 

You will need Seeeduino / Arduino Water Flow Sensor 10K resistor

Wiring up the Water Flow Sensor is pretty simple. There are 3 wires: Black, Red, and Yellow. Black to the Seeeduino's ground pin Red to Seeeduino's 5v pin The yellow wire will need to be connected to a 10k pull up resistor.and then to pin 2 on the Seeeduino.

Here is a fritzing diagram I made to show you how to wire it all up

 

Once you have it wired up you will need to upload the following code to your Seeeduino. Once it is uploaded and you have some fluid flowing through the Water Flow Sensor, you can open the serial monitor and it will display the flow rate, refreshing every second.

 

// reading liquid flow rate using Seeeduino and Water Flow Sensor from Seeedstudio.com
// Code adapted by Charles Gantt from PC Fan RPM code written by Crenn @thebestcasescenario.com
// http:/themakersworkbench.com http://thebestcasescenario.com http://seeedstudio.com

volatile int NbTopsFan; //measuring the rising edges of the signal
int Calc;                               
int hallsensor = 2;    //The pin location of the sensor

void rpm ()     //This is the function that the interupt calls 
{ 
  NbTopsFan++;  //This function measures the rising and falling edge of the 

hall effect sensors signal
} 
// The setup() method runs once, when the sketch starts
void setup() //
{ 
  pinMode(hallsensor, INPUT); //initializes digital pin 2 as an input
  Serial.begin(9600); //This is the setup function where the serial port is 

initialised,
  attachInterrupt(0, rpm, RISING); //and the interrupt is attached
} 
// the loop() method runs over and over again,
// as long as the Arduino has power
void loop ()    
{
  NbTopsFan = 0;      //Set NbTops to 0 ready for calculations
  sei();            //Enables interrupts
  delay (1000);      //Wait 1 second
  cli();            //Disable interrupts
  Calc = (NbTopsFan * 60 / 7.5); //(Pulse frequency x 60) / 7.5Q, = flow rate 

in L/hour 
  Serial.print (Calc, DEC); //Prints the number calculated above
  Serial.print (" L/hour\r\n"); //Prints "L/hour" and returns a  new line
}

I hope this helps someone out! Thank's to Seeed Studio for hooking me up with a sensor so I could develop this tutorial.