Introduction: Automatic FAN ON Using Arduino and DHT11

Hello All

This is my first post on Instructables, and since I learn a lot here, I decided to contribute with one of my experiences using Arduino, sensors and motors. I didn’t create anything new; I just take some tutorials and put everything together with a “small” intelligence. Basically we have one Arduino Mega, with a DHT 11 Sensor, connected with a Servo motor a DC Motor and a LCD.

Step 1: Arduino DHT11 / LCD / SERVO / DC MOTOR and Some Intelligence Using IF > and IF


What you need:



LCD 16x2 + Potentiometer

DHT11 + 10k resistor

SERVO Motor (Im using a SG90)

DC Motor (Im using and old USB Fan)

220ohms Resistor for the DC Motor + P2N222A + 1N4148

Some creativity and humor to make a sign and fit into the SERVO MOTOR. Also a white board and a small box to fix the SERVO.

Step 2: Resume

The idea is show the temperature in the LCD and also in a
white board using a handmade sign connected to the servo motor. If the temperature goes low then 29 Celsius, the servo writes to pin 3 to go 180o if > 29 stays in 90o and if > then 30 Celsius it goes to 10o.

The bonus here is when the temperature reaches more then 30 Celsius, a DC Motor starts to work (in this case a old USB Fan) and try to change the DHT11 more cool.

When less than 30 Celsius the DC Motor still stays on till less than 29 Celsius.

As you can see in the pictures, Im using a Arduino Mega with a Ethernet Shild, but in this case there is no use for the Ethernet Shield.


You can follow my Fritzing scheme here. But for a better understanding of each process is good to search for the amazing instructables avaiable here just focused in each part of the process like the LCD connections, Servo, DC, DHT 11, try to search for this topics for more details.


Thats all! Hope everyone have fun with this.