Sensor specifications:
Alcohol sensor module MQ-2 is used to measure the concentration of flammable gases and smoke in the air. It is successfully used for measuring propane-butane (LPG) , hydrogen (H2), methane (CH4), and smoke (CO) at concentrations of 300-10000ppm. It is powered by a voltage of 2.5V to 5V, with a current consumption of approximately 150mA. The board features a circuit providing two output interfaces – analog and digital. The analog output generates a voltage signal corresponding to the detected ethanol concentration. The digital output operates on a trigger principle – when a specific trigger threshold is crossed, a high output level (logic 1) is produced. The trigger threshold corresponds to a certain concentration of flammable gas and is adjustable via a potentiometer.
Wiring diagram (when using an Arduino-type microcontroller):

Applications of the sensor module MQ-2:
· Household flammable gas leak detector
· Portable gas detector
Additional information: