Fire Detection

What is Needed?

Flame Sensor or Temperature Sensor



  1. Flame Sensor or Temperature Sensor and Buzzer
  2. Connections
  3. Program
  4. Output

What is a Flame Sensor & How it is working?

flame detector is a sensor designed to detect and respond to the presence of a flame or fire, allowing flame detection. Responses to a detected flame depend on the installation, but can include sounding an alarm, deactivating a fuel line (such as a propane or a natural gas line), and activating a fire suppression system. When used in applications such as industrial furnaces, their role is to provide confirmation that the furnace is working properly; in these cases they take no direct action beyond notifying the operator or control system. A flame detector can often respond faster and more accurately than a smoke or heat detector due to the mechanisms it uses to detect the flame.

The pin configuration of this sensor is shown below. It includes four pins which include the following. When this module works with a microcontroller unit then the pins are

  • Pin1 (VCC pin): Voltage supply rages from 3.3V to 5.3V
  • Pin2 (GND): This is a ground pin
  • Pin3 (AOUT): This is an analog output pin (MCU.IO)
  • Pin4 (DOUT): This is a digital output pin (MCU.IO)


These sensors are used in several dangerous situations which include the following.

  • Hydrogen stations
  • Industrial heating
  • Fire detection
  • Fire alarm
  • Fire fighting robot
  • Drying systems
  • Industrial gas turbines
  • Domestic heating systems
  • Gas-powered cooking devices

What is Temperature Sensor & How it is Working?

temperature sensor is a device which is used for measuring the temperature of anything or any place. In temperature sensors, RTD (resistance temperature detector) elements are used for measuring a temperature which is made by wrapping a fine wire around a ceramic or glass. Normally, copper, nickel or platinum wire is for RTD elements. The thermocouple is also used in temperature sensors which are made from two different materials and generates a voltage when a temperature is changed. These voltages are directly proportional to temperature means when a temperature is increased then the voltage is also increased, similarly when a temperature is decreased then voltages is also decreased.

Different Types of Temperature Sensor

Normally six types of temperature sensors are currently used in market,

Thermocouple: This is a most common type temperature sensor and is abbreviated by TC. This is very low-cost, self-powered and voltage generates temperature sensor means its voltages change are changed by changing temperature. It could be used for long distance and different type of thermocouple type sensor are available in the market for different distance. The thermocouple type temperature sensor is shown in figure 2.Figure 2 Thermocouple Type Temperature Sensor

Figure 2 Thermocouple Type Temperature Sensor

Resistance Temperature Detector (RTD): Resistance temperature detector sensor works on the principle of resistance change by changing temperature. Resistance is directly proportional to temperature and has a wide range of temperature measurements capabilities. These are more accurate temperature sensor and have ranged between -270 C0 to 850 C0Figure 3 Resistance Temperature Detector (RTD)

Figure 3 Resistance Temperature Detector (RTD)

Thermistors: This is the third type of temperature sensor which is less costly as compared to other types and is very easy to use. The working principle of a thermistor type temperature sensor is same as RTD type temperature sensor means resistance is changed by changing temperature. These are made with nickel or any ceramic type material. The thermistor type temperature sensor is shown in figure 3.Figure 4 Thermistor Type Temperature Sensor

Figure 4 Thermistor Type Temperature Sensor

Thermometer: It is a device which is used to measure the temperature of any glass solids or liquids. In this type mercy or alcohol is used in a tube whose volume is changed by changing the temperature. Its volume is directly proportional to temperature. Thermometer type temperature sensor is shown is figure 5Figure 5 Thermometer Type Temperature Sensor

Figure 5 Thermometer Type Temperature Sensor

IR Sensors: These are an electronic and non-contacting sensor which have a certain characteristic such that it can detector emits the IR radiations. Normally two types of IR sensors are currently used in a market first one is an infrared sensor and second one is a quantum infrared sensor. It detects the temperature by merit of radiations. the Its cost depends on its working capabilities means it accuracy level depends upon its cost in other works low cost has low accuracy level and high cost have high accuracy level. IR sensor is shown in figure 6Figure 6 IR Type Temperature Sensor


  • Transit
  • HVAC
  • Power and Utilities
  • Calibration and Instrumentation
  • Heat Exchangers
  • Industrial Processes
  • Drilling
  • Heating/cooling systems
  • Laboratory
  • Energy

What is a Buzzer?

The buzzer consists of an outside case with two pins to attach it to power and ground. … When current is applied to the buzzer it causes the ceramic disk to contract or expand. Changing the This then causes the surrounding disc to vibrate. That’s the sound that you hear.


·       Connect Flame Sensor’s VCC to 2nd pin.

·       Connect Flame Sensor’s Ground(GND) to 6th pin.

·       Connect Flame Sensor’s Digital Out(D0) to 8th pin.

·       Connect Buzzer’s Positive(S) to 10th pin.

·       Connect Buzzer’s Negative (-) to 9th pin.


#add a Raspberry Pi GPIO access Library
import RPi.GPIO as GPIO
#initiall all warnings are false

#setup the pin input or output
GPIO.setup(8, GPIO.IN)
#loop for continues running
while True:
#get the input from 8th pin
# Check the getting input High or Low
if a==GPIO.HIGH:
# If its getting input is High, Buzzer is ON
#if its getting input is LOW, Buzzer is LOW

Detect Fire

Now let’s run the code!

When you run the code it will show whether the Status is Normal or Fire

If the status is Fire then the Buzzer will start Ringing.

Real-Time Use cases

  • House and Apartments
  • Commercial Buildings
  • Schools and Colleges
  • Offices and Shopping Malls

Are you ready for Innovation?

Post your New Innovative projects using the same sensor and Win Exiting PRIZES and More!!!

Reach us at

Social media & sharing icons powered by UltimatelySocial