MQ-135 Air Quality Sensor

MQ-135 air quality sensor unit is an electronic device used to detect a wide range of gases and air pollution in the surrounding environment. This sensor allows electronic circuits, such as Arduino, to read the concentration of different gases in the air, making it ideal for air quality monitoring applications, gas leak alarms, and smart ventilation systems. This unit operates at 5 volts, and contains two outputs: a digital output and an analog output. The analog output provides a voltage reading proportional to the gas concentration in the air, while the digital output gives a signal when the gas concentration exceeds a certain threshold that can be adjusted via a variable resistor on the unit. Technical details: operating voltage: 5 volts, warm-up time: approximately 20 seconds, detectable gases: suitable for detecting liquefied petroleum gas (LPG), butane, propane, methane, smoke, alcohol, gasoline, carbon dioxide (CO₂), and other harmful gases.