MQ-135 Air Quality Sensor Module

Well, detecting air quality is getting more important as we need to take care the only Earth that we have. And with the increasing air and environmental pollution, this MQ135 Air Quality Sensor Module will be a good assistant and provide useful information about the surrounding air.

This is sensor module based on MQ135 gas sensor uses in clean air low conductivity tin oxide (SnO2). It comes with basic components to enable the sensor to function properly and hook up easily to any controller that you preferred. When the sensor is kept in their environment, the conductivity in the sensor increases with the air pollution in gas concentration increases.

By using a simple circuitry converts the conductivity changes to analog voltage corresponding to the gas concentration. MQ135 Air Quality Sensor Module for ammonia, sulfide , benzene vapor high sensitivity of the smoke and other harmful monitor is also very good. This sensor can be used to measure a variety of harmful gases and also a low-cost sensors for a variety of applications .

For Arduino, connect DO to any digital pin (if you want it in digital input). Connect AO at analog pin (if you want it in analog input).

MQ135 Spec:

• Detection of gas: Ammonia /Sulfide/ Benzene vapor
• Detection of Concentration:10-1000ppm
• Input voltage: DC 5V
• Power consumption (current): 150mA
• AO output: 0.1-0.3V (relatively non-polluting), the highest concentration voltage is about 4V

Note: After the sensor is energized, it needs to be preheated for about 20S, and the measured data is stable. The heating of the sensor is a normal phenomenon, because there is a heating wire inside.

• Wide detecting scope
• Fast response and High sensitivity
• Stable and long life
• Operating Voltage is +5VDC
• Detect/Measure NH3, NOx, alcohol, Benzene, smoke, CO2, etc.
• Analog output voltage: 0V to 5V
• Digital output voltage: 0V or 5V (TTL Logic)
• Preheat duration 20 seconds
• Can be used as a digital or analog sensor
• The Sensitivity of digital output can be adjusted using on board potentiometer
• The TTL output valid signal is low. (When the output is low, the signal light is on, it can be directly connected to the MCU or relay module)
• The voltage of the analog output, the higher the concentration, the higher the voltage.
• Arduino compatible
• Comes with 4 mounting screw holes (M3 or 3mm size)
• Product dimensions: 32 (L) * 20 (W) * 22 (H)