The project described here is a simple Arduino Based Data Logger which can be used at any place where data is need to be stored for further processing and monitoring.
The project posted here basically store temperature, humidity with date and time in regular interval on a SD card or on a computer or on both. The wide range of operation and data rate of 12 samples per minutes make this circuit more versatile and attractive at the same time. The data logging can be adjusted as per desire by changing the delay function in the program.
Circuit Description of Arduino Based Data Logger
The circuit of Arduino Based Data Logger shown in figure 1, employs four main particular electronics components i.e. Arduino Uno Board, Real Time Clock Module (RTC DS3231), SDcard Module and Temperature and humidity sensor module (DHT-11). An Arduino Uno Board is the heart of this project. Arduino Uno Board have 14 digital pins and 6 analog pins out of which all the pin can be used for input and output.
For date and time, we had utilized a RTC (Real Time Clock) module. The module we had used here is DS3231. This module is equipped with real-time clock IC. The various functions of RTC module DS3231 are calendar, 24-hour and 12-hour time format with AM and PM indication. The two pins SDA and SCL of DS3231 module is connected to analog pin A4 and A5 of arduino uno board respectively as shown in circuit diagram. This module is equipped with 3-volt CMOS bottom cell thus no need of external power supply to run RTC module internally.
For storing data (date, time, temperature and humidity) we had used MicroSD card. For interfacing MicroSD card with Arduino UNO we had used a MicroSD card module. The four lines CS, MOSI, MISO and SCK of MicroSD card is connected to digital pin 4, 11, 12 and 13 of arduino uno board respectively as shown in figure 1.
A temperature and humidity sensor module DHT-11 is used here to monitor temperature and humidity of environment. The output of this sensor is digital in nature thus DOUT pin of DHT-11 is connected to digital pin 7 of arduino uno board.
All the module used in this project (RCT Module, SD card Module and Temperature and humidity sensor module DHT-11) is powered using arduino board. The arduino uno board gets its input voltage from 9V power supply through DC jack line.
PARTS LIST OF ARDUINO BASED DATA LOGGER
Arduino Uno Board
RTC Module – DS3231
Temperature and Humidity Sensor – DHT-11
MicroSD Card Module
Software Code: The software code for Arduino Based Data Logger is written in Arduino Programming Language and is burn in Arduino Uno Board using Arduino IDE. You can directly download software code folder from the link given below. The folder contains DHT-11 Sensor Library and software code.
Working of the project Arduino Based Data Logger:
The working procedure of the project is summarizing in few points shown below:
- Connect all the circuit as shown in circuit diagram.
- Burn the program on arduino uno board using arduino IDE
- Wait few seconds for initialization of sensor module.
- Temperature, humidity with date and time is stored on SD card in .txt format. (log.txt)
- Connect the SD card module to computer and open Log.txt. The Log.txt file looks like below image when opened.