Data Sheet

HANWEI ELETRONICS CO.,LTD MQ-2 http://www.hwsensor.com
TEL: [phone] 67169080 FAX: [phone] E-mail: [e-mail]
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.
Electric parameter measurement circuit is shown as Fig.2
E. Sensitivity characteristic curve
Fig.2 sensitivity characteristics of the MQ-2
SENSITVITY ADJUSTMENT
Resistance value of MQ-2 is difference to various kinds and various concentration gases. So,When using
this components, sensitivity adjustment is very necessary. we recommend that you calibrate the detector for
1000ppm liquified petroleum gas<LPG>,or 1000ppm iso-butane<i-C4H10>concentration in air and use value of
Load resistance that( R
L
) about 20 KΩ(5KΩ to 47 KΩ).
When accurately measuring, the proper alarm point for the gas detector should be determined after
considering the temperature and humidity influence.
MQ-2
0.1
1
10
100 1000 10000
ppm
Rs/Ro
H2
LPG
CH4
CO
alcohol
smoke
propane
air
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
-20 -10 0 10 20 30 40 50 60
degree
Rs/Ro
33%RH
85%RH
Fig.3 is shows the typical
sensitivity characteristics of
the MQ-2 for several gases.
in their: Temp: 20℃、
Humidity: 65%、
O
2
concentration 21%
RL=5kΩ
Ro: sensor resistance at 1000ppm of
H
2
in the clean air.
Rs:sensor resistance at various
concentrations of gases.
Fig.4 is shows the typical dependence of
the MQ-2 on temperature and humidity.
Ro: sensor resistance at 1000ppm of H
2
in air
at 33%RH and 20 degree.
Rs: sensor resistance at 1000ppm of H
2
at different temperatures and humidities.
Fig.4