Data Sheet
HANWEI ELETRONICS CO.,LTD   MQ-2   http://www.hwsensor.com 
TEL: 86-371- 67169070 67169080 FAX: 86-371-67169090               E-mail: sales@hwsensor.com
TECHNICAL DATA   
 MQ-2  GAS SENSOR
 FEATURES 
 Wide detecting scope Fast response and High sensitivity 
 Stable and long life Simple drive circuit 
 APPLICATION 
 They are used in gas leakage detecting equipments in family and industry, are suitable for detecting 
 of LPG, i-butane, propane, methane ,alcohol, Hydrogen, smoke. 
 SPECIFICATIONS 
 A. Standard work condition 
Symbol  Parameter name  Technical  condition  Remarks 
 Vc  Circuit voltage  5V±0.1  AC OR DC 
 V
H 
Heating voltage  5V±0.1  ACOR DC 
 R
L 
Load resistance  can adjust   
 R
H 
Heater resistance 
33Ω±5% 
Room Tem 
 P
H 
Heating consumption  less than 800mw   
 B. Environment condition 
Symbol  Parameter name  Technical condition  Remarks 
 Tao  Using Tem 
-20℃-50℃ 
 Tas  Storage Tem 
-20℃-70℃ 
 R
H 
Related humidity  less than 95%Rh 
 O
2 
Oxygen concentration  21%(standard condition)Oxygen 
concentration can affect sensitivity 
minimum  value is 
over 2% 
 C. Sensitivity characteristic 
Symbol  Parameter name   Technical parameter  Remarks 
Rs  Sensing 
Resistance 
   3KΩ-30KΩ 
  (1000ppm iso-butane ) 
 α
(3000/1000) 
 isobutane 
Concentration 
 Slope  rate 
    ≤0.6 
Standard 
Detecting 
Condition 
   Temp: 20℃±2℃  Vc:5V±0.1 
   Humidity: 65%±5%   Vh: 5V±0.1 
Preheat time           Over 24 hour 
Detecting concentration 
scope: 
200ppm-5000ppm 
LPG and propane 
300ppm-5000ppm 
 butane 
5000ppm-20000ppm 
 methane 
300ppm-5000ppm H
2 
100ppm-2000ppm 
 Alcohol 
 D. Structure and configuration, basic measuring circuit 
 Structure and configuration of MQ-2 gas sensor is shown as Fig. 1 (Configuration A or B), sensor composed by 
micro AL2O3 ceramic tube, Tin Dioxide (SnO2) sensitive layer, measuring electrode and heater are fixed into a 
     Parts  Materials 
1
Gas sensing 
 layer 
SnO
2 
2
Electrode  Au 
3
Electrode line  Pt 
4
Heater coil  Ni-Cr alloy 
5
Tubular ceramic 
Al
2
O
3 
6
Anti-explosion 
network 
Stainless steel gauze
(SUS316 100-mesh)
7
Clamp ring  Copper plating Ni 
8
Resin base  Bakelite 
9
Tube Pin  Copper plating Ni 
A向
A向
Fig. 1 
Configuration A
Configuration B
Fig.2 


