Contents
How does MQ 135 sensor work?
The MQ-135 gas sensor senses gases like ammonia nitrogen, oxygen, alcohols, aromatic compounds, sulfide, and smoke. The boost converter of the chip MQ-3 gas sensor is PT1301. The operating voltage of this gas sensor is from 2.5V to 5.0V. It has the potential to detect different harmful gases.
What is MQ in MQ sensor?
MQ2 is one of the commonly used gas sensors in MQ sensor series. It is a Metal Oxide Semiconductor (MOS) type Gas Sensor also known as Chemiresistors as the detection is based upon change of resistance of the sensing material when the Gas comes in contact with the material.
What can MQ 135 detect?
The MQ-135 Gas sensor can detect gases like Ammonia (NH3), sulfur (S), Benzene (C6H6), CO2, and other harmful gases and smoke. Similar to other MQ series gas sensor, this sensor also has a digital and analog output pin.
Why is the mq135 gas sensor so sensitive?
When the target combustible gas exists, the sensor’s conductivity is higher along with the gas concentration rising. Convert change of conductivity to correspond output signal of gas concentration. MQ135 gas sensor has high sensitivity to Ammonia, Sulphide and Benzene steam, also sensitive to smoke and other harmful gases.
How does the mq-135 sensor work in Clean Air?
Simply assemble the circuit as this. MQ-135 Module sensor has lower conductivity in clean air. When the target combustible gas exists, the sensor’s conductivity is higher along with the gas concentration rising. Convert change of conductivity to correspond output signal of gas concentration.
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.