Zhengzhou Winsen Electronics Technology Co., Ltd
www.winsen-sensor.com
Tel: 86-371-67169097/67169670 Fax: 86-371-60932988 Email:
MQ135 Semiconductor Sensor for Air Quality
Profile
Sensitive material of MQ135 gas sensor is SnO
2,
which with lower conductivity in clean air. When
target pollution gas exists, 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.
MQ135 gas sensor has high sensitivity to ammonia
gas, sulfide, benzene series steam, also can monitor
smoke and other toxic gases well. It can detect kinds
of toxic gases and is a kind of low-cost sensor for
kinds of applications.
Features
It has good sensitivity to toxic gas 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 alarm, industrial gas alarm and portable gas detector.
Technical Parameters
Stable.1
Model
MQ135
Sensor Type
Semiconductor
Standard Encapsulation
Bakelite, Metal cap
Target Gas
ammonia gas, sulfide,
benzene series steam
Detection range
10
～
1000ppm( ammonia gas,
toluene, hydrogen, smoke)
Standard Circuit
Conditions
Loop Voltage
V
c
≤24V 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
29Ω±3Ω (room tem.)
Heater consumption
P
H
≤950mW
Sensitivity
S
Rs(in air)/Rs(in 400ppm H
2
)≥5
Output Voltage
Vs
2.0V
～
4.0V
（
in 400ppm H
2
）
Concentration Slope
α
≤0.6(R
400ppm
/R
100ppm
H
2
)
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
Over 48 hours
Fig1.Sensor S
tructure
Unit: mm
NOTE: Output voltage (Vs) is V
RL
in test environment.