The MQ5 Gas Sensor module is useful for gas leakage detecting. It can detect LPG, i-butane, methane, alcohol, Hydrogen, smoke and so on. The sensitivity can be adjusted using the on-board potentiometer, and you'd use this sensor by reading the analog pin to which it is connected. Please use these sensors only in controlled experiments! Combustible gases and fumes are very dangerous! Here are details for some MQ gas sensor.
Sysmbol
MQ-2
MQ-3
MQ-5
MQ-9
Detect Gas
Combustible Gas, Smoke
Alcohol Vapor
LPG, Natural Gas, Town Gas
Carbon Monoxide, Coal Gas, Liquefied Gas
Detect Concentration
300-10000ppm
0.04-4mg/L Alcohol
300-10000ppm
10-1000ppmCO;100-10000PPm Gas
Specification
Working voltage: 5V
Working Current: 150mA
DO: TTL output
AO: Analog output, it will be higher with more such gas.