EDISON SCIENCE CORNER: LPG LEAKAGE DETECTOR USING ARDUINO AND OLED DISPLAY

in this blog, I am going to build an LPG detector with alarm.

watch this making video

An LPG gas sensor is one kind of device which is used to sense the presence of an LPG gas leak in the home, cars, storage tanks. This sensor is attached to an alarm circuit to give an alert to the peoples through a buzzer sound in the area where the gas leak is occurring.

How does mq2 gas sensor work?

every mq2 sensor is made with a heating element and it is coated with some chemicals that are responsible for the detection of gasses
Sensitive material of MQ-2 gas sensor is SnO2, which with lower conductivity in clean air. When the target combustible gas exists, The sensor’s conductivity is higher along with the gas concentration rising. using simple electronic circuit, we can convert change of conductivity to correspond output signal of gas concentration. MQ-2 gas sensor has a high sensitivity to LPG, Propane and Hydrogen, also could be used to Methane and other combustible steam, it is with low cost and suitable for different application.

MQ2 gas sensor is an electronic sensor used for sensing the concentration of gases in the air such as LPG, propane, methane, hydrogen, alcohol, smoke and carbon monoxide. ... Concentrations of gas in the gas is measured using a voltage divider network present in the sensor. This sensor works on 5V DC voltage.

MQ2 Gas sensor works on 5V DC and draws around 800mW. It can detect LPG, Smoke, Alcohol, Propane, Hydrogen, Methane and Carbon Monoxide concentrations anywhere from 200 to 10000ppm.

Things needed for making LPG detector

Arduino nano

mq2 gas sensor
128*64 OLED display
buzzer
2 led
dot board

circuit diagram

The MQ2 sensor has four pins two pins are used for interfacing with development board and other two pins are used GND and Vcc.

Out of the two interfacing pins one is analog output and other is digital pin. Connect Vcc of the buzzer to 5V pin of Arduino and connect GND to GND. Then place a 128 × 62pixel OLED display. It has four pins two for I2C communication. Connect Vcc of OLED to Vcc of Arduino and connect GND to GND. Then connect SDA toA4 of Arduino and SCD to A5. These are the I2C pins of Arduino. Attach a buzzer and LED to the board.

this is the simplest circuit we are just using the analog read function of arduino

. Then we convert that value into 0-100%by maping... Very simple

download code from here

WORKING

The output analog value of the sensor varies according to the gas concentration. At first the display is initialized. The output of the sensor varies with respect to the concentration of the gas and the microcontroller reads it accordingly. As the analoge reads the value ranging from 1-5 the leakage is within the limit and hence a message “No Leakage detected” is displayed on the screen. If the value exceeds 5 and the analogue reads a value ranging between 5-20, an appreciable leakage is detected. At this time, two digital outputs are considered which is LED and buzzer.

A message “Leakage detected” is displayed on the screen and the buzzer. As the values increases further, for a range ≥35-<45, a message “Don’t Lit” is displayed on the LED and for leakage above 45 the message “Danger” is displayed, along with a high frequency sound which is supported to alert us on the leakage

I used common pcb to solder all componets

After completing the circuit and tesing i made a simple case for detector i used 3 mm form sheet to build this .. this is very easy and efficient way.