IoT based Air Pollution Monitoring System using Arduino

Mithilesh Pandey's picture

Offline

Joined: Oct 14, 2020

Replies: 5
IoT based Air Pollution Monitoring System using Arduino
October 14, 2020 - 11:24am

Hi All,

Recently I went through the Project Idea "IoT-based Air Pollution Monitoring System using Arduino ( https://circuitdigest.com/microcontroller-projects/iot-air-pollution-monitoring-using-arduino ) " published on circuitdigets.com. Here I found some discrepancies w.r.t the article and circuit diagram image. In the article, for connecting Wi-Fi module ESP826 to Arduino, the author has mentioned that the RX pin of the esp8266 to the pin 9 of Arduino, and the TX Pin of ESP8266 to pin 10 of Arduino. However, in the diagram (Image) pin connections are shown as different.

So, KIndly clarify this section. We have already finalized the project. 

Thanks in advance. 

Regards,

Mithilesh Pandey

 

Aswinth Raj's picture

Offline

Joined: Aug 16, 2016

Replies: 973
Interfacing ESP8266 with Arduino
October 14, 2020 - 3:08pm

Please follow the circuit diagram, the ESP8266 communicates using software serial to Arduino. In the Arduino program as you can see in the below line

SoftwareSerial esp8266(9,10); // This makes pin 9 of Arduino as RX pin and pin 10 of Arduino as the TX pin

Pin 9 and 10 of Arduino is defined as Rx and Tx respectively, so we just have to connect Tx of ESP to pin 9 and Rx of ESP to pin 10. You can always change these values in the program if required  

Mithilesh Pandey's picture

Offline

Joined: Oct 14, 2020

Replies: 5
Dear Aswinth Raj,
October 14, 2020 - 3:28pm

Dear Aswinth Raj,

Thanks for the reply. I will follow your suggestion while integrating components for making the system. 

regards,

Mithilesh Pandey

 

Mithilesh Pandey's picture

Offline

Joined: Oct 14, 2020

Replies: 5
Project Description mismatch with diagram (Image)
October 19, 2020 - 3:55pm

Hello Ashwinth Raj,

I have done all the required wiring and uploaded the code. Done calibration of MQ135 for 5 hours (I know it has to be done for at least 12 hours, I aborted it to further check all the functionality). 

LCD screen is also functioning as expected. But after connecting to WiFi (ESP8266) I'm not getting a web page showing sensor data as mentioned in the article. 

 

Kindly suggest what is missing from my side? I have done a voltage divider using three 1K resistors as per the diagram.

 

 

 

 

 

 

Mithilesh Pandey's picture

Offline

Joined: Oct 14, 2020

Replies: 5
Project Description mismatch with diagram (Image)
October 19, 2020 - 5:13pm

Hello Ashwinth Raj,

I used URL http://192.168.4.1/test and the page has started opening on a mobile phone browser. However, I need to calibrate the sensor for perfect reading. I have calibrated it for 5 hours to get RZERO value. The same has been added in the MQ135.h file also. But the display is showing only 2.95 PPM which must be incorrect. How to get rid of this issue? Please guide. 

 

Regards,

Mithilesh Pandey

Aswinth Raj's picture

Offline

Joined: Aug 16, 2016

Replies: 973
MQ sensor with Arduino
October 20, 2020 - 11:37am

Using MQ sensor with Arduino is a bit tricky, I have never found them to be accurate. Also make sure you do 24 hrs pre-heating. If you want a detailed understanding I would suggest you to read this 

https://circuitdigest.com/microcontroller-projects/arduino-mq137-ammonia...

This is a different MQ sensor that measures ammonia, but the procedure for all MQ sensor remains the same.