Smoke Detection and Exhaust Fan Control with LCD Display

Introduction

Ensuring safety in enclosed spaces is of paramount importance, especially in areas prone to smoke and pollutants. A smoke detection and exhaust fan control system with an LCD display can play a crucial role in maintaining air quality. In this article, we will explore the working principle, components required, circuit diagram, and how to implement such a system using an Arduino.

Working Principle

The basic principle behind this system is to detect smoke or elevated levels of airborne particles using a smoke sensor. When smoke is detected, the system activates an exhaust fan to remove the polluted air, simultaneously displaying the status on an LCD screen.

Things We Need

To build this system, you will need the following components:

1. Smoke sensor (MQ-2 or similar)
2. Arduino board (e.g., Arduino Uno)
3. LCD display (16x2 or similar)
4. Relay module
5. Exhaust fan
6. Power supply
7. Jumper wires
8. Breadboard
9. Resistors (for voltage level shifting, if needed)

Circuit Diagram

Working of the System with Arduino

1. Connecting the Components: First, connect the smoke sensor, Arduino, relay module, and LCD display according to the circuit diagram. Ensure that all connections are secure.
2. Programming the Arduino: Write the Arduino code to read data from the smoke sensor and control the relay module and LCD display. The code should include logic to trigger the exhaust fan when the smoke levels exceed a predefined threshold. Here's a simplified example:

Arduino Code

#include <LiquidCrystal.h>
 
LiquidCrystal lcd(12, 11, 5, 4, 3, 2); // Initialize LCD
 
int smokeSensorPin = A0; // Smoke sensor analog pin
int relayPin = 10; // Relay control pin
int threshold = 500; // Adjust this threshold value as needed
 
void setup() {
  lcd.begin(16, 2); // Initialize LCD
  pinMode(relayPin, OUTPUT);
}
 
void loop() {
  int smokeLevel = analogRead(smokeSensorPin);
 
  lcd.clear(); // Clear the LCD display
  lcd.setCursor(0, 0);
  lcd.print("Smoke Level:");
 
  if (smokeLevel > threshold) {
    digitalWrite(relayPin, HIGH); // Turn on exhaust fan
    lcd.setCursor(0, 1);
    lcd.print("Smoke Detected!");
  } else {
    digitalWrite(relayPin, LOW); // Turn off exhaust fan
    lcd.setCursor(0, 1);
    lcd.print("No Smoke");
  }
 
  delay(1000); // Delay for stability
}

1. Upload the Code: Upload the code to your Arduino board using the Arduino IDE.
2. Testing: Place the smoke sensor near a source of smoke (e.g., incense) and observe the system's response. When the smoke level exceeds the threshold, the exhaust fan should activate, and the LCD will display "Smoke Detected."

Conclusion

A smoke detection and exhaust fan control system with an LCD display can help maintain indoor air quality and enhance safety. By combining a smoke sensor, Arduino, relay module, and LCD display, you can create an effective and responsive system. Remember to adjust the threshold value in the code to suit your specific environment and requirements. With this project, you have taken a significant step towards creating a safer and healthier living or working space.