Contents
How does the MQ-135 sensor work?
MQ – 135 Air Quality Sensor The air quality sensor detects ammonia, nitrogen oxide, smoke, CO2, and other harmful gases. The air quality sensor has a small potentiometer that permits the adjustment of the load resistance of the sensor circuit. The 5V power supply is used for air quality sensor.
How do you calibrate a MQ 135 sensor?
While using the library-supported Arduino setup, MQ-135 gas sensor calibration is done at first by finding the value of Ro in fresh air, and then using that value to find Rs through the formula: Rs = (Vcc/VRL-1)x RL, that means Rs = (5V/(sensorValue * (5.0/1023.0))-1)*RL.
How do you calibrate a MQ-135 sensor?
How to interface mq-135 gas sensor with Arduino?
In this article, you will see how to interface MQ-135 sensor to Arduino and read Co2 levels in the atmosphere. According to need, you can display the CO2 levels on Serial Monitor or LCD. I made this article simple and easy to understand so that beginners can also understand. Before getting started you must know about MQ-135.
Is the mq-135 gas sensor sensitive to CO2?
According to need, you can display the CO2 levels on Serial Monitor or LCD. I made this article simple and easy to understand so that beginners can also understand. Before getting started you must know about MQ-135. MQ-135 is a gas sensor which is sensitive to CO2.
How to use mq-135 gas sensor-codrey electronics?
Since sense resistance (Rs) value of MQ-135 gas sensor is different for various kinds and various concentration of gases, sensitivity adjustment becomes very necessary. The datasheet recommends to calibrate the MQ-135 sensor for 100ppm NH3 or 50ppm Alcohol concentration in air and use value of the load resistor (RL) about 20KΩ (10KΩ to 47KΩ).
What are the sensitivity characteristics of the mq-135?
The above figure shows shows the typical sensitivity characteristics of the MQ-135 for several gases. in their: Temp: 20, Humidity: 65%, O2 concentration 21%, RL=20kΩ, Ro: sensor resistance at 100ppm of NH3 in the clean air. Rs:sensor resistance at various concentrations of gases.