The (MQ5) module is a Gas Sensor, with it you can find gas leaks with ease (in homes and industry). It can be used to find alcohol, H2, LPG, CH4, and other substances. Due to its great sensitivity and short reaction time, measurements can be made as quickly as is practical. As the detection is reliant on a variation in the sensing material's resistance when the Gas comes into contact with it, it is a Metal Oxide Semiconductor (MOS) type Gas Sensor, commonly known as Chemiresistors.

Package Includes:

• 1x MQ5 LPG Sensor Module

Features:

• Indication of the signal output.
• Dual signal output (analog output, and TTL level output)
• The TTL output signal is low. (When low output signal light, and can be connected directly to the microcontroller)
• 0 ~ 5V analog output voltage, the higher the concentration, the higher the voltage.
• Liquefied petroleum gas, natural gas, city gas, have better sensitivity.
• Has a long life and reliable stability
• Fast response and recovery characteristics
• Operating voltage: DC 5 V
• The MQ-5 Sensor can detect LPG and CH4 between 300 to approximately 10000ppm.
•  It may be used to detect H2, CO, and alcohol.

Description:

The (MQ5) module is a Gas Sensor, with it you can find gas leaks with ease (in homes and industry). It can be used to find alcohol, H2, LPG, CH4, and other substances. Due to its great sensitivity and short reaction time, measurements can be made as quickly as is practical. As the detection is reliant on a variation in the sensing material's resistance when the Gas comes into contact with it, it is a Metal Oxide Semiconductor (MOS) type Gas Sensor, commonly known as Chemiresistors, a heating element is Included in the MQ-5 Sensor to detect flammable gas successfully. On the other hand, placing a heating source next to combustible gas may be dangerous. The Sensor has a stainless steel mesh anti-explosion network consisting of two thin layers as a result. This stainless steel mesh has a heating element.

Principle of Work:

The power LED turns on when the module is powered. The MQ5 operates by detecting the amount of LPG in the environment. The sensor's analog pin then provides an analog signal corresponding to the concentration of LPG in the environment. The majority of MCUs have an integrated ADC that can be used to read the analog output of an LPG gas sensor and perform signal processing to transform the observed analog voltage into the amount of LPG in the air. We can take the appropriate actions, such as setting off an alarm, based on this measurement. The MQ5 LPG sensor's digital output pin is the same. The digital pin turns HIGH and the built-in light for the digital output illuminates when LPG gas is detected.

Pinout of the Module:

the MQ5 LPG Sensor Module has 4 pins, two of which are for VCC and Gnd and the other two can output analog and digital data simultaneously. The module's working voltage range is 5V with a tolerance of 0.1%, so we are powering the circuit using the Arduino's 5V port. the module features two internal LEDs. The power LED turns on when the board is powered up, and the doubt LED turns on when the trigger value set by the potentiometer is reached. The analog signal from the gas sensor's input is converted to a digital signal on this board by the integrated comparator OP-Amp. We also have a Trim-pot that enables us to adjust the sensitivity of the device. We also have a number of resistor capacitors for decoupling and filtering.

Applications:

Environmental Monitoring Systems

The environmental air monitoring system can provide a suitable monitoring method that uses an MQ5 sensor. This is a lightweight, customer-friendly, and low-cost air monitoring device that can measure LPG gas we can use this anywhere

Methane and LPG Testing/Detecting Devices

Through this system, we can immediately collect information on methane, and we can also display other gases which can be processed by any microcontroller, and the results on the OLED display

LPG Gas Leakage Detecting Equipment

The goal of detecting a gas leak is to prevent the worst potential causes of the gas leak, using the above type of MQ sensor. The choice of the MQ5 sensor is because of the nature of MQ5 which is suitable for detecting natural gas.

Circuit:

Connect and integrate the MQ5 Gas LPG Sensor with the Arduino UNO using the circuit shown above. By copying and pasting the code, you may upload it to your Arduino IDE. The next step is to upload the code to the Arduino UNO. watch the readings on the Serial monitor. use the sensor with LPG from an oven or a lighter to check the abrupt changes in readings. As a result, the adjustments are visible on the serial monitor. and the LED will turn on if the value of the digital out is 1.

Library:

This Module doesn't need any Library to function.

Code:

#define MQ5pin 0
float sensorValue; //variable to store sensor value
void setup() {
 pinMode(13,1);
 Serial.begin(9600); // sets the serial port to 9600
 Serial.println(" MQ5 warming up!");
 delay(20000); // allow the  MQ5 to warm up
}
void loop() {
 sensorValue = analogRead( MQ5pin); // read analog input pin 0
 Serial.print("Sensor Value: ");
 Serial.println(sensorValue);
 if(digitalRead(8)){
 digitalWrite(13,1);
 }else{
 digitalWrite(13,0);
 }
 delay(2000); // wait 2s for next reading
}

Technical Details:

• Item Weight: 10.0 grams
• Heater Voltage: 5.0V
• Power Supply: 5 Volts
• Interface Type: Analog & Digital
• Working Current: 150mA
• DOUT: TTL output
• AOUT: Analog output
• Preheat time: Over 20s
• Heater Resistance: 31±10%
• Adjustable Resistance
• Sensing Resistance Range: 10 – 60K
• Sensor Heat Consumption: 0.5-800mW
• Detecting Concentration: 200-10000ppm

Resources:

MQ-5.pdf 

Comparisons:

The MQ series Gas sensors are the most frequently used ones when it comes to measuring or detecting a specific Gas. Both the sensor and the module for these sensors are available for purchase. Since it includes an op-amp comparator and a digital out pin, you can purchase it as a module if all you're trying to do is detect the presence of a gas rather than measure its ppm. But it is advised to purchase the sensor alone if you intend to monitor a gas' ppm levels (without a module). the MQ4 IS sensing range of 300-10000 PPM is suitable for methane gas leak detection and also for also to Propane and Butane but the MQ5 Sensor can detect LPG (Liquified Petroleum Gas), methane, propane, butane, natural gas, and city gas, with low sensitivity to alcohol and smoke so we prefer using MQ5 with gas detections systems in homes.