MQ-7 Carbon Monoxide Gas Sensor

This MQ7 Gas Sensor is another MQ Gas Sensors family Metal Oxide Semiconductor (MOS) type Gas Sensor. Its primary application is to detect carbon monoxide. This sensor has a sensing element that is mostly aluminium-oxide-based ceramic that has been coated with Tin dioxide (SnO2) and is enclosed in a stainless-steel mesh. When CO gas comes into contact with the sensing element, the element's resistivity changes. The difference is then measured to determine the concentration of gases present. The MQ7 Sensor contains a small heating element required to preheat the sensor before it can be used. It can detect carbon monoxide gas levels in the air ranging from 20 PPM to 2000 PPM. The simple analogue voltage interface of the sensor requires only one analogue input pin from your microcontroller.