Carbon Monoxide gas sensor module for Arduino MQ-7

What is the KY-015 DHT11 Module?

The KY015 is a temperature and humidity module for Arduino and other microcontroller projects

 

KY-015 module has a DHT11digital temperature and humidity sensor and a resistor. The DHT11 uses a thermistor for the temperature sensing and a capacitive humidity sensor along with an internal IC to give a digital output for both temperature and humidity.

 

Voltage : 3.3 to 5VDC

Humidity range : 20% to 90% @ 5% RH accuracy

Temperature range : 0C to 50C at 2C accuracy

Size 30x15mm

 

How Can I use the KY-015 Module to monitor temperature and humidity?

Here is an example project to measure temperature and humidity using the KY015 module and an Arduino Uno

 

Temperature and Humidity Sensor

In this project, we will be building a weather station that can measure both temperature and humidity.

This is what you will need:

Tools

Jumper Leads (male to female)

 

Components

Arduino Uno x 1 or Arduino Nano x 1

KY-15 sensor module

 

Libraries

DHT Sensor Library

Adafruit Unified Sensor Library

 

Step 1

First you will nedd to assemble the project. Connect everything together using the wiring diagram bellow for reference.

 

 

Connect the KY-015 sensor module to the Arduino

KY-015                        Arduino   

Ground - - - - - - - - - -  Ground
Vcc - - - - - - - - - - - - - - 3v3
Data - - - - - - - - - - - - -  A0

A 10KΩ pull-up resistor is built in to the KY-015

 

Step 2

Connect your Arduino to the PC and install the above Libraries. If you don’t know how to do this, CLICK HERE and follow the “Installing Arduino Libraries” section.

 

Step 3

We can now create the code to get this all working

First, delete the code in the IDE window, then include the aforementioned libraries:  

#include "DHT.h"

This bit of code imports the DHT library and links it to the sketch.

#define DHTPIN A0
#define DHTTYPE DHT11

This bit of code defines which pin is KY015 connected to and sets the type of sensor (KY015 uses DHT11)

DHT dht(DHTPIN, DHTTYPE);

This bit of code initialises the sensor

void setup() {
  Serial.begin(115200);
  Serial.println(F("DHT11 test!"));
  dht.begin();
}

The setup bit of code initialises serial output with baud rate of 115200 and prints DHT11 test! In the console

void loop() {
	  delay(2000);

This bit makes the Arduino wait 2 seconds between measurements

  float h = dht.readHumidity();

Read humidity from the sensor

  float t = dht.readTemperature();

Read temperature from the sensor

  Serial.print(F("Humidity: "));
  Serial.print(h);
  Serial.print(F("%  Temperature: "));
  Serial.print(t);
  Serial.println(F("°C "));
}

Print the latest reading in serial monitor

 

#include "DHT.h"

#define DHTPIN A0     // Digital pin connected to the DHT sensor
#define DHTTYPE DHT11   // DHT 11
DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);
  Serial.println(F("DHT11 test!"));

  dht.begin();
}

void loop() {
  delay(2000);

  float h = dht.readHumidity();
  float t = dht.readTemperature();

  Serial.print(F("Humidity: "));
  Serial.print(h);
  Serial.print(F("%  Temperature: "));
  Serial.print(t);
  Serial.println(F("°C "));
}

 

A sensitive ethanol sensor will detect levels of alcahol in the air. The level of alcohol varies the output voltage. A comparator gives a digital output. When the ethanol level reaches a certain level, this can be set with the built in potentiometer.

Sensitivity : 0.4mg/L alcohol

Size 32x21mm

 

This module has a sensitive methane sensor that will detect levels of methane in the air. The sensor outputs a varying voltage on the analogue pin depending on the level of methane and it has a comparator to give you a digital out at when the methane level reaches a certain level, this can be set with the built in potentiometer.

 

Please note, this sensor needs to warm up for 20 seconds before it will give a stable reading.

 

Voltage : 5VDC

Current : 150mA

Sensitivity : 300 to 10000ppm

Size 32x21mm

 

This tiny module has a BMP180 precision pressure sensor soldered on to a GY-68 breakout board to make it easy to use this amazing sensor. The BMP180 will give you accurate pressure data via the standard I2C protocol making it simple to add to your project.

 

Voltage : 1.8 - 3.6VDC

Preasure Range 300hPa to 1100hPa (-500m to 9000m)

Current consumption 0.5µA

Size 13x10mm

This module uses the DS1307 chip, which can be used for keeping time in a very wide variety of projects. For example it can be used to add time stamps to sensor readings, display the time accurately or keep track of time even when there is no power supplied (although it will require a rechargeable CR2032 battery for this). The Tiny RTC supports the I2C protocol, which makes it very easy to interface with many microcontrollers. 

 

Specs: 

VCC:  5V DC

Battery (optional): CR2032

Power consumption: <500nA (in Battery Backup Mode)

RAM: 56 Byte, non-volatile

Memory: 32kb EEPROM

Dimensions: 27mm x 28mm x 8.4mm

 

 

This module has a sensitive gas sensor that can measure the air quality. It can measure gaseous compounds and elements such as ammonia (NH3), nitrogen oxides (NOx) carbon dioxide (CO2), benzene (C6H6) and other harmful gases. The sensor outputs a varying voltage on the analogue pin depending on the level of pollutants and it has a comparator to give you a digital output when the level of pollutants reaches a certain level. This can be set with the built-in potentiometer.

 

Please note, this sensor needs to warm up for a couple of minutes before it will give a stable reading.

 

Voltage : 5VDC

Current : 150mA

Sensitivity : 300 to 10000ppm

Size 32x21mm

 

This module has a sensitive gas sensor that can measure smoke and various combustible gases. It can measure compunds such as LPG, Propane, Methane and smoke. The sensor outputs a varying voltage on the analogue pin depending on the level of gases present and it has a comparator to give you a digital output when the level of combustible gases reaches a certain level. This can be set with the built-in potentiometer.

 

Please note, this sensor needs to warm up for a couple of minutes before it will give a stable reading.

 

Voltage : 5VDC

Current : 150mA

Sensitivity : 300 to 10000ppm

Size 32x21mm