The MQ-3 gas sensor module,with high sensitivity to ethanol, can resist the interference of gasoline, smog, vapor, detect ethanol in the air sensitively. The material of MQ-3 gas sensor is SnO2 ,which has low conductivity in clean air. With a 3p line connecting Arduino sensor shield , through Arduino mega168 controller programming, you can make ethanol alarm, alcohol tester with buzzer module and relay module.

Specifications:
1, detection range: 10-100ppm ethanol
2, characteristic gas: 125ppm ethanol
3, heating voltage: 5 + - 0.2 V (AC·DC)
4, loop voltage:≤24V DC
5, load resistance: adjustable
6, voltage in clean air: ≤1.5 V
7, sensitivity: Rin air/Rin typical gas≥5
8 ,recovery time: ≤30S
9, service life: 5 years
10, size: 20.5 mm x 41mm