YFS201

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YFS201 Water Flow Sensor Module

Table of Contents

1. Introduction
2. Features
3. Installation
4. Usage
5. Mathematical Formulation
6. Examples
7. Caution
8. Important Notes
9. Warning
10. License

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Introduction

The YFS201 Water Flow Sensor Module is an Arduino-compatible library designed to interface with the YF-S201 water flow sensor. This sensor measures the flow rate of water using the Hall Effect principle, generating pulses proportional to the flow rate. This library provides an easy-to-use interface to read the flow rate, calculate the total volume of water, and integrate with other components like LCDs, relays, or SD cards.

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Features

• Flow Rate Measurement: Accurately measure the flow rate of water in liters per minute (L/min).
• Total Volume Calculation: Calculate the total volume of water that has passed through the sensor.
• Pulse Counting: Count the number of pulses generated by the sensor to determine flow rate.
• Compatibility: Works seamlessly with Arduino boards and other compatible microcontrollers.
• Extensible: Easily integrate with other libraries for LCDs, SD cards, or IoT platforms.

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Installation

To use the YFS201 library, follow these steps:

1. Download the library as a ZIP file or clone the repository.
2. Open the Arduino IDE.
3. Go to Sketch > Include Library > Add .ZIP Library and select the downloaded file.
4. Include the library in your sketch:

   #include "yfs201.h"

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Usage

Basic Setup

1. Connect the YF-S201 sensor to your Arduino:

   • VCC to 5V
   • GND to GND
   • Signal to a digital pin (e.g., D2).

2. Initialize the sensor in your sketch:

   const int flowSensorPin = 2; // Pin connected to the sensor
   yfs201 flowSensor(flowSensorPin);
   
   void setup() {
       Serial.begin(9600);
       flowSensor.begin();
   }

3. Read the flow rate and total volume in the loop() function:

   void loop() {
       float flowRate = flowSensor.getFlowRate();
       unsigned long totalPulses = flowSensor.getTotalPulses();
   
       Serial.print("Flow Rate: ");
       Serial.print(flowRate);
       Serial.println(" L/min");
   
       Serial.print("Total Pulses: ");
       Serial.println(totalPulses);
   
       delay(1000); // Wait 1 second before reading again
   }

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Mathematical Formulation

The flow rate $$Q$$ (in liters per minute) is calculated using the following formula:

$$ Q = \frac{f \times 60}{K} $$

Where:

• $$Q$$: Flow rate in liters per minute (L/min).
• $$f$$: Frequency of pulses in Hertz (Hz).
• $$K$$: Sensor calibration factor (typically 7.5 for YF-S201).

The total volume $$V$$ (in liters) is calculated by integrating the flow rate over time:

$$ V = \int_{0}^{t} Q , dt $$

In the code, this is approximated as:

$$ V = \sum_{i=1}^{n} \left( \frac{Q_i \times \Delta t_i}{60} \right) $$

Where:

• $$Q_i$$: Flow rate at time interval ( i ).
• $$\Delta t_i$$: Time elapsed since the last measurement (in milliseconds).

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Examples

Example 1: Basic Flow Rate Measurement

This example reads the flow rate and displays it on the Serial Monitor.

#include "yfs201.h"

const int flowSensorPin = 2;
yfs201 flowSensor(flowSensorPin);

void setup() {
    Serial.begin(9600);
    flowSensor.begin();
}

void loop() {
    float flowRate = flowSensor.getFlowRate();
    Serial.print("Flow Rate: ");
    Serial.print(flowRate);
    Serial.println(" L/min");
    delay(1000);
}

Example 2: Total Volume Calculation

This example calculates and displays the total volume of water that has passed through the sensor.

#include "yfs201.h"

const int flowSensorPin = 2;
yfs201 flowSensor(flowSensorPin);

float totalVolume = 0;
unsigned long lastTime = 0;

void setup() {
    Serial.begin(9600);
    flowSensor.begin();
    lastTime = millis();
}

void loop() {
    unsigned long currentTime = millis();
    unsigned long elapsedTime = currentTime - lastTime;
    lastTime = currentTime;

    float flowRate = flowSensor.getFlowRate();
    float volumeIncrement = (flowRate * elapsedTime) / 60000.0;

    totalVolume += volumeIncrement;

    Serial.print("Total Volume: ");
    Serial.print(totalVolume);
    Serial.println(" L");

    delay(1000);
}

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Caution

• Ensure the sensor is properly connected to avoid damage to the Arduino or sensor.
• Do not exceed the maximum flow rate specified in the sensor's datasheet (typically 30 L/min for YF-S201).

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Important

• The calibration factor $$K$$ may vary depending on the specific sensor. Always calibrate the sensor for accurate measurements.
• The sensor is not suitable for measuring non-conductive fluids.

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Warning

• Electrical Safety: Always disconnect power before making changes to the circuit.
• Water Safety: Avoid exposing the sensor to water temperatures above its rated limit (typically 60°C).

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License

This project is licensed under the MIT License. See the LICENSE file for details.

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