Sensitive material of MQ-3 gas sensor is SnO2, which with lower conductivity in clean air. When the target alcohol gas exist, The sensor’s conductivity is more higher along with the gas concentration rising.Please use simple electrocircuit, Convert change of conductivity to correspond output signal of gas concentration.
MQ-3 gas sensor has high sensitity to Alcohol, and has good resistance to disturb of gasoline, smoke and vapor. The sensor could be used to detect alcohol with different concentration, it is with low cost and
suitable for different application.