Flammable Gas Sensor
（Model：MQ-2）
Manual
Version: 1.6
Valid from: 2021-07-01
Zhengzhou Winsen Electronics Technology Co., Ltd
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caused by misuse, please read the manual carefully and operate it correctly in accordance with the
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Zhengzhou Winsen Electronics Technology CO., LTD.
Zhengzhou Winsen Electronics Technology Co., Ltd www.winsen-sensor.com
Tel: 86-371-67169097/67169670 Fax: 86-371-60932988 Email: sales@winsensor.com
Leading gas sensing solutions supplier in China!
MQ-2 Semiconductor Sensor for Flammable Gas
Profile
Sensitive material of MQ-2 gas sensor is SnO
2,
which with lower
conductivity in clean air. When the target flammable gas exist, the
sensor’s conductivity gets higher along with the gas concentration rising.
Users can convert the change of conductivity to correspond output signal
of gas concentration through a simple circuit.
MQ-2 gas sensor has high sensitivity to propane and smoke, also can
detect the natural gas and other flammable steam well. It is with low cost
and suitable for different applications of detecting kinds of flammable
gases.
Features
It has good sensitivity to propane, smoke &etc in wide range, and has advantages such as long lifespan,
low cost and simple drive circuit &etc.
Main Applications
It is widely used in domestic gas leakage alarm, industrial flammable gas alarm and portable gas detector.
Technical Parameters Stable.1
Fig1.Sensor Structure
Unit: mm Tolerance:±0.1mm
Model
MQ-2
Sensor Type
Semiconductor
Standard Encapsulation
Bakelite, Metal cap
Target Gas
Flammable gas, smoke
Detection range
300～10000ppm(flammable gas)
Standard Circuit
Conditions
Loop Voltage
V
c
5.0V±0.1V DC
Heater Voltage
V
H
5.0V±0.1V AC or DC
Load Resistance
R
L
Adjustable
Sensor character
under standard
test conditions
Heater Resistance
R
H
30Ω±3Ω（room temp.）
Heater consumption
P
H
≤950mW
Sensitivity
S
Rs(in air)/Rs(2000ppm C
3
H
8
)≥5
Output Voltage
Vs
2.5V～4.0V（in 2000ppmC
3
H
8
）
Concentration Slope
α
≤0.6(R
3000ppm
/R
1000ppm
C
3
H
8
)
Standard test
conditions
Tem. Humidity
20℃±2℃；55%±5%RH
Standard test circuit
Vc:5.0V±0.1V；
V
H
:5.0V±0.1V
Preheat time
Not less than 48 hours
O2 content
21%（not less than 18%）
O2 concentration effects initial value,
sensitivity and repeatability.
Lifespan
10 years
NOTE: Output voltage (Vs) is V
RL
in test environment.
Fig1.Sensor Structure
Unit: mm Tolerance:±0.1mm
