MQ4 Module

The MQ-4 module is based on the MQ4 Methane gas sensor as a gas sensing element. MQ-4 sensor is ideal for detection or measuring of Natural gas CNG concentration at a range from 300 to 10000ppm.  It offers very good sensitivity and fast response to Methane and also shows small sensitivity to alcohol & smoke makes it ideal for use in natural gas monitoring systems. The module comes with basic components integrated allowing the sensor to function properly. And interfaced easily to any controller as the user prefers. Hence no external components are required, we need to just plug in Vcc & ground pins and you are ready to go.

MQ4 module consists of both digital and analogue outputs. This module not only provides a binary indication of the presence of combustible gases but also an analogue representation of their concentration in air. When gas is detected using the digital output, the indicator LED D0 turns ON. As a result, the digital pin will go from logic high to logic low 0V. The presence of onboard LM393 comparator IC in the MQ4 module compares the adjustable preset value and also eliminates the need for an external microcontroller. Simply power up the module and set the sensitivity of the digital pin using the potentiometer. So when the module detects the gas the digital pin will go low. MQ4 natural gas sensor module can be easily interfaced to any Microcontroller, Arduino, or even Raspberry Pi.

While using the analogue pin to measure PPM, the TTL drove (0-5V) analogue pins read values using a microcontroller that calculates the resistance value. By using the external load resistance the resistance variation is converted into a suitable voltage variation. This will be directly proportional to the concentration of the gas to which the sensor detects.