MQ-135 Gas Sensor and Air Quality Control Module

MQ-135 Gas Sensor Module – Air Quality & Gas Detection

The MQ-135 Gas Sensor Module is a high-sensitivity air quality control sensor designed to detect a wide range of harmful gases and volatile compounds in the environment. It is especially effective in monitoring air pollution in homes, offices, and industrial applications. The module can detect gases like NH₃, NOₓ, alcohol, benzene, smoke, and CO₂, making it a popular choice for smart environmental monitoring systems.

Its compact size and compatibility with popular microcontrollers such as Arduino, ESP32, and Raspberry Pi make it ideal for DIY air quality stations, HVAC systems, smart homes, and safety applications.

Applications:

• Indoor air quality monitoring systems

• Smart home ventilation control

• Air purifiers and filtration systems

• IoT-based environmental sensors

• Industrial gas leak detection

• Educational & DIY electronics projects

Features:

• Detects a wide range of gases and pollutants

• Ideal for indoor air quality monitoring

• Dual analog and digital outputs for flexibility

• Adjustable sensitivity via onboard potentiometer

• Fast response and recovery time

• Long lifespan and stable performance

• Compact size, perfect for embedded projects

Specifications:

• Sensor Type: MQ-135 (semiconductor gas sensor)

• Operating Voltage: 5V DC

• Working Current: 150mA

• Pin Number: 4 Pins

• Detectable Gases: NH₃, NOₓ, alcohol, benzene, smoke, CO₂, etc.

• Analog Output: 0 – 5V

• Digital Output: TTL logic (via comparator onboard)

• Preheat Time: 20 seconds (typical)

• Sensitivity Range: 10ppm – 1000ppm

• Operating Temperature: -10°C to +50°C

• Humidity Range: ≤ 95% RH

• PCB Dimensions: ~32mm x 20mm

• Interface Type: Analog + Digital (DO + AO)

• Mounting: Breadboard & case-compatible module format