The gas sensitive material used in MQ-8 gas sensor is SnO2, which is of lower electrical conductivity in clean air.
When there is hydrogen in the environment where sensor resides, the electrical conductivity of the sensor increases with the increase of the hydrogen concentration in the air.
The change of electrical conductivity can be converted to the output signal corresponding to that of the gas concentration by using a simple circuit.
The sensitivity of MQ-8 gas sensor to hydrogen is quite high, it can also detect a variety of other gases containing hydrogen.
This sensor is suitable for a variety of applications, is definitely a good catch.
Feature
- good sensitivity to hydrogen in a wide range of concentrations.
- long service life, low cost
- simple drive circuit
Specification
- Detectable concentration: 100-1000ppm (hydrogen)
- Operating voltage: 5V
- Heating voltage VH: 5.0V±0.1V AC or DC
- Load resistance RL: adjustable
- Heating resistance RH: 29±3Ω(Room temperature)
- Heating power: PH ≤900mW
- Sensitivity S: Rs(in air)/Rs(1000ppm H2)≥5
- Output voltage Vs: 2.5-4.0V（1000ppm H2）
- Concentration slope: α≤0.6(R1000ppm/R400ppm H2)
- Temperature ; humidity: 20℃±2℃；55%±5%RH
- Standard test circuit: Vc:5.0V±0.1V；VH: 5.0V±0.1V
Connection Diagram
Sample Code
///Arduino Sample Code
void setup()
{
Serial.begin(9600); //Set serial baud rate at 9600 bps
}
void loop()
{
int val;
val=analogRead(0);//Read Gas value from analog 0
Serial.println(val,DEC);//Print the value to serial port
delay(100);
} |
Application
- household gas leak alarm
- Industrial-level hydrogen alarm
- Portable gas detector