MQ135 Gas Sensor Module

(Including GST)

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. When the level of these gases go beyond a threshold limit in the air the digital pin goes high. This threshold value can be set by using the on-board potentiometer. The analog output pin, outputs an analog voltage which can be used to approximate the level of these gases in the atmosphere. The MQ135 air quality sensor module operates at 5V and consumes around 150mA. It requires
some pre-heating before it could actually give accurate results.

Application:MQ135 Gas Sensor Module

Used as air quality monitors.
Used as a domestic air pollution detector.
Used in the detection of excess or leakage of gases

11 People watching this product now!

SKU: A87474 Category: Gas Sensors

Description

MQ135 Gas Sensor Module is made using Air Quality Gas Sensor MQ135. It is a low-cost semiconductor sensor and has high sensitivity to ammonia gas, sulphide, benzene series steam, also can monitor smoke and other toxic gases well. It is a Metal Oxide Semiconductor (MOS) type Gas Sensor also known as Chemin resistors as the detection is based upon change of resistance of the sensing material when the Gas comes in contact with the material. Using a simple voltage divider network, concentrations of gas can be detected. This module provides both digital and analog outputs. It can be easily interfaced with Microcontrollers, Arduino Boards, Raspberry Pi etc.

Features – MQ135 Gas Sensor Module

Wide detecting scope
Fast response and High sensitivity
Stable and long-life Simple drive circuit
Used in air quality control equipment for buildings/offices, is suitable for detecting of NH3,NOx, alcohol, Benzene, smoke, CO2, etc.
Size: 35mm x 22mm x 23mm (length x width x height)
Signal output instruction.
Dual signal output (analog output, and high/low digital output)
8. 0 ~ 4.2V analog output voltage, the higher the concentration the higher the voltage

Specifications – MQ135 Gas Sensor Module

Operating Voltage: 2.5V to 5.0V
Power consumption: 150mA
Detect/Measure: NH3, Nox, CO2, Alcohol, Benzene, Smoke
Typical operating Voltage: 5V
Digital Output: 0V to 5V (TTL Logic ) @ 5V Vcc
Analog Output:0-05 V@ 5V Vcc

Technical details: – MQ135 Gas Sensor Module

The MQ135 is one of the popular gas sensors from the MQ series of sensors that are commonly used in air quality control equipment. It operates from 2.5V to 5.0V and can provide both digital and analog output.
Note that all MQ sensors have to be powered up for a pre-heat duration for the sensor to warm up before it can start working.
This pre-heat time is normally between 30 seconds to a couple of minutes. When you power up the module the power LED will turn on, leave the module in this state till the pre-heat duration is completed

Pin Configuration:- MQ135 Gas Sensor Module

VCC: It is used to connect 5V to the sensor.
GND: It is used to connect GND to the sensor.
DO: It is a digital output Pin. From this pin, you will get digital data HIGH/LOW.
The digital output pin of the sensor can be used to detect harmful gases in the environment. The sensitivity of the digital pin can be controlled by using the 10k potentiometer. If the gas is detected the indicator LED D0 will turn on and the digital pin will go from logic high to logic
low (0V). The LM393 Op-Amp Comparator IC is used to compare the actual gas value with the value set using the potentiometer. If the actual gas value increases than the set value then the digital output pin gets low.

Pin Configuration: MQ-135 Gas sensor Module

Because of the onboard LM393 comparator IC the MQ135 Gas sensor module can also be used without the need of an external microcontroller. Simply power up the module and set the sensitivity of the digital pin using the potentiometer, then when the module detects the gas the
digital pin will go low. This digital pin can directly be used to drive a buzzer or LED with the help of simple transistors. AO: It is analog output Pin. From this pin, you will get analog data. The Analog output pin of the sensor can be used to measure the PPM value of the required gas. To do this we need to use an external microcontroller. The microcontroller will measure the value of analog voltage and perform some calculations to find the value of Rs/Ro where Rs is the
sensor resistance when gas is present and Ro is sensor resistance at clean air.