MQ-6 gas sensor

 

 

Description:

This is a simple-to-use liquefied petroleum gas (LPG) sensor, suitable for sensing LPG (composed of mostly propane and butane) concentrations in the air. The MQ-6 can detect gas concentrations anywhere from 200 to 10000ppm.

Working Principle:

The MQ6 sensor is the main sensing component which is used in a gas detection appliance. The sensor consist of a sensing material which ionize the gases which comes in its contact. As a result, the ionization process of the gases changes the resistance across the circuit.

Features:

  • High sensitivity to LPG, iso-butane, propane
  • Small sensitivity to alcohol, smoke.
  • Fast response
  • Stable and long life
  • Simple drive circuit

 

Link to datasheet:

https://www.sparkfun.com/datasheets/Sensors/Biometric/MQ-6.pdf

 

 

Do’s and Don’ts:

  • Water Condensation Indoor conditions, slight water condensation will influence sensors’ performance lightly. However, if water condensation on sensors surface and keep a certain period, sensors’ sensitive will be decreased.
  • Used in high gas concentration No matter the sensor is electrified or not, if it is placed in high gas concentration for long time, sensors characteristic will be affected. If lighter gas sprays the sensor, it will cause extremely damage.
  • Long time storage The sensors resistance will drift reversibly if it’s stored for long time without electrify, this drift is related with storage conditions. Sensors should be stored in airproof bag without volatile silicon compound. For the sensors with long time storage but no electrify, they need long galvanical aging time for stability before using.
  • Long time exposed to adverse environment No matter the sensors electrified or not, if exposed to adverse environment for long time, such as high humidity, high temperature, or high pollution etc., it will influence the sensors’ performance badly.
  • Vibration Continual vibration will result in sensors down-lead response then break. In transportation or assembling line, pneumatic screwdriver/ultrasonic welding machine can lead this vibration
  • Concussion If sensors meet strong concussion, it may lead its lead wire disconnected.

 

Applications:

  • Gas leak detection system
  • Fire/Safety detection system
  • Gas leak alarm
  • Gas detector

Advantages:

  • High Sensitivity to LPG, iso-butane, propane
  • Detection Range: 100 – 10,000 ppm iso-butane propane
  • Fast Response Time

Disadvantages:

  • Small sensitivity to alcohol, smoke

 

Schematic:

 

PCB details:

Connection with arduino:

  • Vcc: 5v
  • GND: GND
  • A0: Analog pin of arduino
  • D0: Digital pin of arduino:

Arduino Code:

int sensorValue;

int GasSensorPin = 0;   //Gas Sensor Connection

void setup()

{

 Serial.begin(9600);      // sets the serial port to 9600

}

void loop()

{

 sensorValue = analogRead(GasSensorPin);       // read analog input pin 0

 Serial.println(sensorValue, DEC);  // prints the value read

 delay(100);                        // wait 100ms for next reading

}

  Advantages:

  • High Sensitivity to LPG, iso-butane, propane
  • Detection Range: 100 – 10,000 ppm iso-butane propane
  • Fast Response Time

Disadvantages:

  • Small sensitivity to alcohol, smoke