TEMPERATURE AND HUMIDITY MEASUREMENT USING DHT 11

In this project ,I am using DHT 11 temperature and humidity sensor to measure our environment temperature as well as humidity using Arduino (Nano).

SOME OF THE BASIC ELECTRICAL CHARACTERISTICS:

OPERATING VOLTAGE: 3.5V-5V

CURRENT (measurement):0.3 mA

CURRENT (standby):60 micro amps

RANGE:0 to 50 degree Celsius

RESOLUTION: 16bit

SAMPLING PERIOD: >2 ms

Step 1: CREATING SCHEMATIC

In this schematics using an DHT11 sensor with 5k(ohm) pull up resistor for data line.

PINS:

RED WIRE TO +VCC

BLACK WIRE TO GND

YELLOW WIRE WITH 5 K RESISTOR

3rd pin is NO CONNECTION

COMPONENTS NEEDED:

1. Arduino

2. DHT11 temp and humidity sensor

3.5 k ohm resistor

I AM USING DHT11 WITH BUILT IN RESISTOR AND CAPACITOR FOR PULL UP AND SMOOTHENING THE INPUT VOLTAGE RESPECTIVELY.

Step 2: EXPERIMENT TIME-CONNECTIONS

I have been connected the pins accordingly

5v - +VCC

GND - GND

digital pin 2 - DATA PIN

Step 3: EXPERIMENT TIME-CODE

Using Arduino IDE we can program our Arduino board

but first download and install the library for DHT sensors..

the purpose of downloading the library is to reduce the complexity of the code.

I am downloading the library called SIMPLEDHT it is awesome.

after installing the library by clicking install button.

open file-examples- simpledht-dht11 default.

I am using DHT11. if you are using DHT22 there is also an example code below.. RIGHT THERE...

after opening the code. connect the Arduino board to your computer, and select the PORT. and upload the example sketch.

make sure you connect the data pin to digital pin2 of the Arduino..

CODE PART IS DONE

Step 4: EXPERIMENT TIME - SETUP

after uploading the code open the serial monitor.

you will observe that the sensor sends the data.

not much hard right?

Step 5: WORKING

As I said that the sensor sends out 40bits

8bit humidity integer data + 8bit humidity decimal data + 8bit temperature integer data + 8 bit temperature fractional data + 8bit check sum= 40 bits

Example 1: 40 data received:

0011 0101 0000 0000 0001 1000 0000 0100 1101

Calculate： 0011 0101+0000 0000+0001 1000+0000 0000= 0100 1101

Received data is correct

Humidity：0011 0101=35H (hex) =53%RH

Temperature：0001 1000=18H (hex) =24℃.

SOURCE:-

https://media.digikey.com/pdf/Data%20Sheets/Adafruit%20PDFs/DHT11_ProdManual.pdf

THANK YOU GUYS

IF YOU FIND MISTAKES PLEASE WRITE IN COMMENTS.

SO THAT I CAN RECTIFY IT.

BECAUSE I AM A BUDDING ENGINEER.

IN NEXT PROJECT I CAN USE A LCD DISPLAY TO DISPLAY TEMPERATURE.

STAY AWSOME GUYSS...……………..