The connections of the MQ-135 gas sensor with Arduino:
In the world of technology, there are many sensors being used to monitor and control home applications, robotics, industrial automation, and so on. There are different sensors for different purposes. As like human has different sensing capability for a different purpose. In this article, we are focusing on the MQ-135 gas sensor to monitor the environment. mq-135 gas sensor mainly used to measure the volume of NH3, NOx, Alcohol, Benzene, Smoke, CO2.
There are some other members of gas sensors in the MQ family. mq-135 gas sensor popular for Air Quality monitoring.
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mq-135 gas sensor |
In this tutorial, we are going to learn more about the MQ-135 gas sensor, how to interface the MQ-135 Gas Sensor with Arduino Board?
In this tutorial, we will cover the following sections:
- How mq-135 Gas Sensor Works?
- MQ-135 Gas Sensor pinout and datasheet.
- MQ-135 Gas Sensor Features
- How to connect the MQ-135 Gas Sensor with Arduino?
- The MQ-135 Gas Sensor Arduino Code.
How mq-135 gas sensor works?
The gas sensor module consists of a steel exoskeleton under which a sensor component is placed. This sensitive element is subject to the current through the sensitive wire. This current is known as the heating current through which the gases ionize the sensitive material and are absorbed by the sensitive material. It changes the resistance of the sensing element which changes the value of the current carried from it.
mq-135 gas sensor pinout and datasheet:
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mq-135 gas sensor pinout |
- VCC ( +5 volt)
- GND (-)
- Digital Out
- Analog Out
MQ-135 Gas Sensor Features:
- Fast response and High sensitivity
- Wide detecting scope
- Operating Voltage is +5V
- Detect/Measure the volume of NH3, NOx, alcohol, Benzene, smoke, CO2, etc.
- Analog output voltage: 0V to 5V
- Digital output voltage: 0V or 5V (TTL Logic)
- Preheat duration 20 seconds
- Can be used as a digital or analog sensor
- The Sensitivity of the Digital pin can be varied using the potentiometer
How to connect the MQ-135 Gas Sensor with Arduino?
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Circuit Diagram |
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