Air Quality Sensor MQ135

The MQ-135 Air Quality Sensor is a popular sensor module used for detecting air quality and measuring various gases, including ammonia (NH₃), nitrogen oxide (NO), alcohol, benzene, carbon dioxide (CO₂), and smoke. It is commonly used in air quality monitoring applications, environmental monitoring, and industrial control systems. The sensor detects the concentration of benzene, alcohol and smoke in the air, the result can be obtained measuring the voltage on the analog output. The system is supplied with the voltage from 2.5V to 5V. It has a digital and analog output, making it compatible with most of the commissioning modules including Raspberry Pi and Arduino.

Features
Wide detection range for multiple gases.
High sensitivity with fast response time.
Stable performance with long operational life.
Dual analog and digital output options.
Adjustable sensitivity through onboard potentiometer.
Simple drive circuit for easy interfacing.
Compact design with mounting holes for easy installation.
Specifications
Parameter Value
Operating Voltage 5VDC
Power Consumption ≤800mW
Detection Range 10–1000ppm
Analog Output 0–5V
Digital Output 0V or 5V (TTL Logic)
Preheat Time ≥24 hours
Operating Temperature -10°C to 45°C
Storage Temperature -20°C to 70°C
Humidity Range <95%RH Heater Resistance 33Ω±5% Load Resistance Adjustable Dimensions 35mm x 22mm x 23mm