Project name:- Automatic temperature controlled Fan.
I am going to make an automatic temperature controlled fan .For this we need some hardware component mention below.
- Computer
- Arduino
- Thermistor
- Resistor
- DC fan
- Jumpers
And arduino software for programming.
This project is based on Thermistor sensor whose value is dependent on the temperature. Basically thermistor are of two types they are NTC (negative temperature control) and PTC (positive temperature control)
In NTC resistance is decreases with the increase in temperature, whereas in PTC resistance is increases with the increase in temperature.In this project we use /ntc type thermistor.
The voltage divider circuit is made in the analog input of arduino between thermistor and 2.2k resistor provided the 5V power supply which is shown in below figure.Voltage dividers are one of the most fundamental circuits in electronics.
int DCmotor =13;
int thermistor =A0;
void setup() {
pinMode(DCmotor,OUTPUT);
pinMode(thermistor,INPUT);
Serial.begin(9600);
}
void loop() {
int value= analogRead(thermistor);
Serial.println(value);
if (value>200)
digitalWrite(DCmotor,HIGH);
else
digitalWrite(DCmotor,LOW);
}
When the temperature is normal the resistance value is exceeds 200 so,the motor is turn off .
When the thermistor is start heating is resistance is start decreasing & when its vaue is fall below 200 motor start to operate.