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मूल्य सूची: Retail Price (B2C) मूल्य सूची
मूल्य सूची: Retail Price (B2C) मूल्य सूची
MQ-135 Air Quality and Hazardous Gas Sensor Module for Ammonia, Benzene, Alcohol, Smoke, and CO2 Monitoring

MQ-135 Air Quality and Hazardous Gas Sensor Module for Ammonia, Benzene, Alcohol, Smoke, and CO2 Monitoring

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ParameterDetailed Specification
Operating Voltage5V DC
Target GasesNH3, NOx, Alcohol, Benzene, Smoke.
Detection Concentration10ppm – 1000ppm
Sensing MaterialTin Dioxide 
Comparator ChipOn-board LM393
Output TypeDual Output: Digital (DO) & Analogue (AO)
Heater Power~800mW
Price
₹ 101.69 ₹ 101.69
(Tax included)

Product Description

Monitor the air you breathe with the MQ-135 Air Quality Sensor Module. This versatile gas sensor is specifically designed to detect a wide array of atmospheric pollutants and hazardous gases, making it the primary choice for indoor air quality monitoring systems. At Robogears, we recommend the MQ-135 for its ability to sense Ammonia ($NH_3$), Nitrogen Oxides ($NO_x$), Alcohol, Benzene, Smoke, and Carbon Dioxide ($CO_2$). The module integrates an LM393 comparator for stable digital switching and a multi-turn potentiometer to calibrate your safety thresholds. Whether you are building an automated ventilation system or a smart city pollution tracker at your Pimpri facility, the MQ-135 provides a cost-effective, multi-gas sensing solution.

Detailed Key Features

  • Wide-Spectrum Pollution Detection: Highly sensitive to common indoor air pollutants, providing a comprehensive "Air Quality Index" (AQI) overview for your environment.

  • Dual Signal Interface: Features a Digital Output (DO) for simple "Good/Bad" air quality alerts and an Analog Output (AO) for real-time concentration graphing and data logging.

  • Adjustable Sensitivity Threshold: The on-board potentiometer allows you to fine-tune the exact pollution level at which the digital alarm should activate.

  • Fast Response & High Stability: The $SnO_2$ sensing layer reacts rapidly to environmental changes and offers a long operational lifespan with consistent performance.

  • Integrated Visual Indicators: Includes a Power LED and a separate Signal LED that triggers instantly when air quality drops below your preset limit.

All Technical Details

  • On-board Signal Conditioning: The LM393 ensures the digital output is a clean square wave, perfect for triggering interrupts on an Arduino, ESP32, or Raspberry Pi.

  • Rugged Construction: Features a dual-layer stainless steel mesh to protect the sensitive internal heating and sensing elements from physical damage and dust.

  • Standard Interface: 4-pin header (VCC, GND, DO, AO) ensures compatibility with standard jumper wires and breadboards.

  • Applications: Household air quality monitors, industrial smoke alarms, portable air purifiers, and automated HVAC control.

Prototyping & Engineering Tips (Robogears Exclusive)

  • The "Burn-In" Period: At our Pimpri workshop, we always emphasize a 24-hour preheat period for new MQ-135 sensors. This "burn-off" phase is critical to stabilize the sensing element for accurate PPM (Parts Per Million) readings.

  • Heater Awareness: It is normal for the sensor to feel warm during operation. The internal heater is necessary to facilitate the chemical reaction between the pollutants and the $SnO_2$ layer.

  • Calibration for $CO_2$: To use the MQ-135 for Carbon Dioxide monitoring, you must calibrate the sensor in "clean air" (approx. 400ppm $CO_2$) to establish a baseline $R_o$ value in your code.

  • Avoid Poisoning: Do not expose the sensor to high concentrations of silicone vapors, grease, or corrosive gases, as these can permanently coat the sensing layer and reduce sensitivity.

Package Includes

  • 1 x MQ-135 Air Quality and Hazardous Gas Sensor Module

Image Disclaimer

Product images are shown for illustrative purposes only. The color of the PCB (typically Blue or Black) or the protective mesh style may vary between batches, but the MQ-135 multi-gas detection performance and 5V compatibility remain as described.