MQ3 Gas Sensor is another one of MQ family of gas sensors which is used to detect the alcohol content from 0.05 mg/L to 10 mg/L. It has a sensing element made of Tin Dioxide (SnO2) which has lower conductivity in clean air but when it comes in contact with alcohol gases the conductivity increases in proportion to the concentration of alcohol present. Thus, this Alcohol Sensor  is a low cost solution to measure the alcohol level, also it is resistant to the disturbances caused by the gasoline, vapour and smoke. The sensor has Analog output corresponding to the concentration of the Alcohol gas present or you can also get Digital Output for a particular concentration using the onboard potentiometer. This module can be used as a portable alcohol detector, Gas level over limit alarm, Breathalyser etc.
 
SPECIFICATIONS
1.Operating Voltage 5V±0.1V
2.Current Consumption 150mA
3.Operating Temperature -10°C to 70°C
4.Simple to use, Low Cost and Fast Response
5.Onboard LEDs for output and power
6.Output sensitivity adjustable for Digital Output
7.Analog output 0V to 5V, Digital Output
8.Stable and Long Life
9.Good Sensitivity to Alcohol Gas
 
PRODUCT DESCRIPTION
Much like other Sensors in MQ Series (MQ 2, MQ 4, MQ 135 etc), this module also has 4 output pins. While connecting it to Arduino Boards, you need to power it by 5V pin and GND pin. You will get the Analog Output according to the concentration of Alcohol present and by using the potentiometer to set a threshold level of Alcohol, you can also get the digital output if the concentration goes beyond the threshold.
 
PACKAGE CONTENTS
1×MQ3 Alcohol Sensor Module
 
ADDITIONAL RESOURCES
Datasheet of MQ3 Sensor
Arduino Project for MQ3 Sensor