Both businesses and homes can lose many important things in fires. The Internet of Things is one of today's growing technologies, and in this scenario I am attempting to solve this problem using IoT technology.
Flame sensors are used to detect a fire by using infrared technology. Infrared bulbs are placed at the front of a flame sensor. This sensor comes in three types:
  1. Analog Out pin [AO]
  2. Digital Out pin [D0]
  3. Both Analog [AO] & Digital out pins [DO]
By reading this article, you will learn how to create a fire alarm system using Arduino UNO R3

Prerequisites for creating this system

Hardware Requirement
Hardware Qty
Arduino UNO R3 1
Flame Sensor 1
Piezo buzzer 1
LED Bulb 1
220-ohm Resistor 1
Jumper Wires -
Software Requirement
Arduino IDE (Integrated Development Environment)
It has three stages for developing this fire detection alarm system.
  1. Connect hardware
  2. Write & upload code to Arduino UNO
  3. Test our developed system

Stage 1 [Connect Hardware]

First, we are connecting a flame sensor, Piezo buzzer and Led bulb to Arduino. Refer to the below diagram for making this connection.
How To Create A Fire Detection AlarmingSystem Using Arduino UNO R3
Pin Configuration
Step 1
Connect a flame sensor to Arduino with a Digital Pin by the below pin configuration:
Pin configuration
Flame Sensor Arduino
VCC------------------------------------> +5V
GND------------------------------------> GND
DO --------------------------------------> Digital pin8
Step 2
Next, connect a Piezo Buzzer to Arduino to make an alarm sound. There is no need to use a resistor for the Buzzer connection.
Pin configuration
Piezo Buzzer Arduino
(+) ---------------------------------------------> Digital pin9
(-) ---------------------------------------------> Digital pin GND
Step 3
Connect Led bulb to Arduino for a flashing light for the fire alert warning.
Pin configuration
Led bulb Arduino
(+) --------------------------------------------> Digital pin10
(-) --------------------------------------------> Digital pin GND
We successfully made the hardware connection :).

Stage 2 [Write and upload code to Arduino]

In this step, write code for Arduino using the Arduino IDE.
  1. Download Arduino software using this link here.
  2. Install and open an Arduino IDE in your PC/Laptop.
  3. Connect your Arduino board to your computer using a USB data cable.
  4. Copy and paste below the code into the Arduino IDE.
    1. #define Fire_sensor 8
    2. #define Buzzer 9
    3. #define Light 10
    4. #define ldelay 500
    5. #define bdelay 500
    6. void setup() {
    7. Serial.begin(9600);
    8. pinMode(Fire_sensor, INPUT);
    9. pinMode(Buzzer, OUTPUT);
    10. pinMode(Light, OUTPUT);
    11. }
    12. void loop() {
    13. if (int a = digitalRead(Fire_sensor) == LOW) {
    14. alert();
    15. } else {
    16. digitalWrite(Buzzer, LOW);
    17. digitalWrite(Light, LOW);
    18. }
    19. }
    20. void alert() {
    21. digitalWrite(Light, HIGH);
    22. digitalWrite(Buzzer, HIGH);
    23. delay(ldelay);
    24. digitalWrite(Light, LOW);
    25. digitalWrite(Buzzer, LOW);
    26. delay(ldelay);
    27. digitalWrite(Light, HIGH);
    28. digitalWrite(Buzzer, HIGH);
    29. delay(ldelay);
    30. digitalWrite(Light, LOW);
    31. digitalWrite(Buzzer, LOW);
    32. delay(ldelay);
    33. digitalWrite(Light, HIGH);
    34. digitalWrite(Buzzer, HIGH);
    35. delay(ldelay);
    36. digitalWrite(Light, LOW);
    37. digitalWrite(Buzzer, LOW);
    38. delay(ldelay);
    39. }
Save and upload this code to the Arduino UNO board. After the code upload is completed, the device can start to detect any fire in a fixed area.

Stage 3 [Test our developed system]

Our developed system can now get ready to detect fire. I am using a match box for making fire to test our fire detection alarm system.
How To Create A Fire Detection AlarmingSystem Using Arduino UNO R3
Finally, the fire detection system gets alarmed and a red light indicates when fire can be detected by a sensor. This system successfully works.