Data Sheet

Resistance of sensor(Rs): Rs=(Vc/VRL-1)×RL
Sensitivity Characteristics
Influence of Temperature/Humidity
Fig.1 shows the typical sensitivity characteristics of Fig.2 shows the typical temperature and humidity
the MQ-2, ordinate means resistance ratio of the sensor characteristics. Ordinate means resistance ratio
(Rs/Ro), abscissa is concentration of gases. Rs means of the sensor (Rs/Ro), Rs means resistance of sensor
resistance in different gases, Ro means resistance of in 1000ppm Butane under different tem. and humidity.
sensor in 1000ppm Hyrogen. All test are under standard Ro means resistance of the sensor in environment of
test conditions. 1000ppm Methane, 20℃/65%RH
Structure
and configuration
Structure and configuration of MQ-2 gas sensor is shown as Fig. 3, sensor composed by micro AL2O3 ceramic tube, Tin
Dioxide (SnO2) sensitive layer, measuring electrode and heater are fixed into a crust made by plastic and stainless steel
net. The heater provides necessary work conditions for work of sensitive components. The enveloped MQ-2 have 6 pin, 4
of them are used to fetch signals, and other 2 are used for providing heating current.
Fig1
0.5
0.7
0.9
1.1
1.3
1.5
1.7
1.9
-20-100 1020304050℃
Rs/R0
60%RH
30%RH
85%RH
Fig2