Arduino Air Sensor

In this project I will be showing how i created a Arduino air sensor that can measure the temperature, humidity, CO2 levels and particulate matter levels

For this project you will need:

1x Arduino UNO

1x DHT11 temperature & humidity sensor

1x SSD1306 0.96" OLED display

1x MH-H14 Co2 sensor

1x PMS5003 particulate matter sensor with cable

1x PMS5003 breakout board

(In my case I mounted the breakout board on a protoshield)

To start this project you will need to get the first things working starting with the DHT11 and OLED.

The SSD1306 OLED is a 0.96 inch display that communicates over the I2C protocol. This way you only have 2 pins to communicate with, this makes the wiring a lot easier.

The DHT11 is a temperature and humidity sensor that is very easy to use. this way you can practice using the screen with it.

The connections are as following:

Arduino.D2 - DHT11.OUT

Arduino.SDA - OLED.SDA

Arduino.SCL - OLED.SCK

VCC on the OLED and DHT11 are connected to 5v

OLED and DHT11 GND are connected to Arduino GND

To add the Co2 sensor we need to connect to pin 6 on the MH-Z14 sensor. In my case i got a board on top of the sensor but I don't think this affects the working of the sensor. This board does come with a cable and connector. However the data cable coming from it is not the one i want to use. I fixed this by rerouting a extra cable to the correct pin. This pin needs to be connected to pin D3 on the Arduino.

The PMS needs to be connected to the RX and TX port of the Arduino. This means that when you reprogram the arduino the IDE will give a error. So I made a protoshield with switches to make it easier to disconnect. I also mounted the PMS breakout board to the protoshield. I have made some connectionpoint on the protoshield to easily connect the sensors but are still connected to the same pins.

The PMS is connected to the 0 and 1 pins of the arduino with the following diagram:

Arduino.TX --- PMS.RX

Arduino.RX --- PMS.TX