How do MQ gas sensors work?
What is MQ2 Gas Sensor? Using a simple voltage divider network, concentrations of gas can be detected. MQ2 Gas sensor works on 5V DC and draws around 800mW. It can detect LPG, Smoke, Alcohol, Propane, Hydrogen, Methane and Carbon Monoxide concentrations anywhere from 200 to 10000ppm.
How does gas leak detector work?
It works by monitoring different gas levels in the air. These devices are generally battery operated and used for safety. Once they detect a higher than normal concentration of gas in the air, they warn people in the location through a series of really hard to miss audible beeps.
What is MQ135 gas sensor?
MQ135 Gas Sensor is an air quality sensor for detecting a wide range of gases, including NH3, NOx, alcohol, benzene, smoke and CO2. Ideal for use in office or factory. MQ135 gas sensor has high sensitivity to Ammonia, Sulfide and Benzene steam, also sensitive to smoke and other harmful gases.
What is the principle of toxic gas detector operation?
A catalytic gas sensor contains a platinum coil and is heated when it comes into contact with gaseous reactants. This raises the temperature within the coil. The catalytic gas sensor will sound the alarm and alert people if that temperature change is within what is considered a dangerous range.
What can the mq-7 gas sensor be used for?
MQ-7 gas sensor has high sensitity to Carbon Monoxide. The sensor could be used to detect different gases contains CO, it is with low cost and suitable for different application. According to its datasheet, the MQ-7 carbon monoxide sensor detects 20 to 2000 ppm of CO in air.
What is the sensitivity of the mq-7 carbon monoxide sensor?
According to its datasheet, the MQ-7 carbon monoxide sensor detects 20 to 2000 ppm of CO in air. Here is its sensitivity characteristic curve: This is a graph of Rs/R0 vs. gas concentration in ppm.
What kind of capacitor is used for mq-7 sensor?
Sensor resistance depends on CO concentration, so voltage changes accordingly. Capacitor C1 is used to smooth input PWM voltage on MQ-7 sensor, the higher is its capacitance the better, but also it has to have low ESR – so ceramic (or tantalum) capacitor is preferred here, electrolytic one won’t perform well.
Is the mq-7 circuit compatible with Arduino?
So that less work is required for integrating it with the arduino, it is recommended that you buy the complete MQ-7 sensor circuit. This you can see below. If you buy the complete board, there are 4 leads which need to be connected. There 4 leads are +5V, AOUT, DOUT, and GND. The +5V and GND leads establishes power for the alcohol sensor.