The gas sensing material used in the MQ-4 gas sensor is the two tin oxide (SnO2), which has a low electrical conductivity in the clean air. When the sensor is in the presence of combustible gas in the environment, the electrical conductivity increases with the increase of the concentration of combustible gas in the air. Using a simple circuit, the electrical conductivity can be converted to an output signal corresponding to that of the gas concentration. MQ-4 gas sensor has high sensitivity to methane, and also has good sensitivity to propane and propane. This sensor can detect many kinds of combustible gases, especially natural gas, is a low cost sensor for many applications.

Suitable for family or factory of methane gas, natural gas and other monitoring devices, can test gas, methane 300 to10000ppm;

Module feature:

1, the use of high quality dual panel design, with power and TTL signal output indicator;

2, with DO switch signal (TTL) output and AO analog signal output;

3, TTL output signal is low level. (when the output is low, it can be directly connected to the microcontroller or relay module).

4, analog output voltage, the higher the concentration of higher voltage.

5, the detection of methane, natural gas has a good sensitivity.

6, four screw holes for positioning;

7, product appearance size: 32 (L) *20 (W) *22 (H)

8, has long service life and reliable stability

9, rapid response recovery characteristics

Electrical performance:

Input voltage: DC5V power (current): 150mA

DO output: TTL number 0 and 1 (0.1 and 5V)

AO output: 0.1-0.3V (relative no pollution), the highest concentration of about 4V

Special remind: sensor is energized, the need to preheat the 20s about, the measured data is stable, heat sensor belongs to the normal phenomenon.) because of the internal electric heating wire, if hot is not normal. 1 X MQ-3 Alcohol Ethanol Sensor Model