Semiconductor Alcohol Sensor MQ303B

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The gas sensitive material used in the MQ303B gas sensor is a semiconductor material with low conductivity in clean air. When there is alcohol vapor in the sensor environment, the electrical conductivity of the sensor increases with the increase of the concentration of alcohol gas in the air. A simple circuit can be used to convert the change in conductivity into an output signal corresponding to the concentration of the gas.


* High sensitivity
* Quick response recovery
* Long life
* Low power consumption
* Low cost
* Small size


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Vehicle Alcohol Test

The picture shows a common "ignition interlock system" with an alcohol detection function in the United States. This lock is connected to the ignition system of the car. Before ignition, the driver must blow air to ensure that the alcohol concentration in the body does not exceed the standard. and the car can start.


Alcohol Detector

Strengthen the punishment of drinking and driving in all the country to reduce the vicious traffic accidents caused by drunk driving. This involves testing a person's alcohol level and using equipment to do the testing. An alcohol detector is an effective tool for measuring the alcohol content in the human body.


Other Detector

Formaldehyde detector is an instrument for detecting formaldehyde. Generally, semiconductor sensors and electrochemical sensors are used to realize the rapid semi-quantification of formaldehyde in indoor air on the spot, which is characterized by simple structure, small size, intuitive,easy to carry and use.


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Specification Product Size

Technical Data Sheet

Model MQ303B
Sensor Type Semiconductor
Standard Encapsulation Metal Cap
Target Gas Alcohol
Detection range 20~500ppm alcohol
Standard Circuit Conditions Loop Voltage VC ≤6V DC
Heater Voltage VH 0.9V±0.1V AC or DC
Load Resistance RL Adjustable
Sensor character under standard test conditions Heater Resistance RH 4.0Ω±0.5Ω (room temp.)
Heater consumption PH ≤140mW
Zero point V0 0.01-0.45V
Sensitivity VS 1.0-2.5V(125ppm alcohol)
Concentration Slope α ≤0.6(R300ppm/R50ppm alcohol)
Standard test conditions Temp.  Humidity 20℃±2℃;55%±5%RH
Standard test circuit VC:3.0V±0.1V
Preheat time Not less than 48 hours


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As a pioneer in gas sensor based solutions with the advanced processes, technologies and products, Winsen offers a wide range of gas sensors:


As a pioneer in gas sensor based solutions with the advanced processes, technologies and products, Winsen offers a wide range of gas sensors:


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