Arduino MQ-9 가스센서

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
  

#include <MQUnifiedsensor.h>

#define         Board                   ("Arduino UNO")
#define         Pin                     (A0)  //Analog input 4 of your arduino
#define         Type                    ("MQ-9") //MQ9
#define         Voltage_Resolution      (5)
#define         ADC_Bit_Resolution      (10) // For arduino UNO/MEGA/NANO
#define         RatioMQ9CleanAir        (9.6) //RS / R0 = 60 ppm 

MQUnifiedsensor MQ9(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin, Type);

void setup() {
  // 가스 센서 시작
  Serial.begin(9600); //Init serial port

  // PPM 농도 및 상수 값을 계산하도록 산술 모형 설정
  MQ9.setRegressionMethod(1); //_PPM =  a*ratio^b
 
  
  MQ9.init(); 
  
  Serial.print("Calibrating please wait.");
  float calcR0 = 0;
  for(int i = 1; i<=10; i ++)
  {
    MQ9.update(); // Update data, the arduino will be read the voltage on the analog pin
    calcR0 += MQ9.calibrate(RatioMQ9CleanAir);
    Serial.print(".");
  }
  MQ9.setR0(calcR0/10);
  Serial.println("  done!.");
  
  if(isinf(calcR0)) {Serial.println("Warning: Conection issue founded, R0 is infite (Open circuit detected) please check your wiring and supply"); while(1);}
  if(calcR0 == 0){Serial.println("Warning: Conection issue founded, R0 is zero (Analog pin with short circuit to ground) please check your wiring and supply"); while(1);}
  
  Serial.println("** Lectures from MQ-9 ****");
  Serial.println("|    LPG   |  CH4 |   CO  |");  
}

void loop() {
  MQ9.update(); // Update data, the arduino will be read the voltage on the analog pin

  MQ9.setA(1000.5); MQ9.setB(-2.186); // Configurate the ecuation values to get LPG concentration
  float LPG = MQ9.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup

  MQ9.setA(4269.6); MQ9.setB(-2.648); // Configurate the ecuation values to get LPG concentration
  float CH4 = MQ9.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup

  MQ9.setA(599.65); MQ9.setB(-2.244); // Configurate the ecuation values to get LPG concentration
  float CO = MQ9.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup

  Serial.print("|    "); Serial.print(LPG);
  Serial.print("    |    "); Serial.print(CH4);
  Serial.print("    |    "); Serial.print(CO); 
  Serial.println("    |");

  delay(1000); //Sampling frequency
}