2. Designing and implementation of temperature
detecting circuit.
After a particular temperature, controlling the
temperature using a fan system.
And also defining a range such that cooling
system will work only in that range.
AIM
3. A temperature sensor is a device which is used to detect the
hotness or coldness of the environment.
Here we are using LM35 (IC) as a temperature detecting
sensor which is having three terminals (Vcc,GND,Output).
LM35 IC is very efficient when compared with thermistor.
Basically this is a semi-conductor based temperature sensor
placed on Integrated Circuits.
INTRODUCTION
4. Arduino UNO
LED
Bread board
9-V DC motor
Liquid Crystal Display
10K Potentiometer
Buzzers
220 Ohm Resistors
COMPONENTS
6. LM35:
LM 35 is an integrated circuit sensor that can be used to measure temp with an electrical
output proportional to temperature. It has VCC, GND and OUTPUT. This sensor provides
variable voltage at the output based on the temperature.
“LM35” provides output in degree Celsius and can sense up to 150 degree Celsius
temperature.
It can measure temperature more accurately then a thermistor. The sensor circuitry is sealed
The sensor circuitry is sealed and not subjected to oxidation.
It also possess low self heating and does not cause more
than 0.1 oc temperature rise in still air.
The operating temperature range is from -55°C to 150°C
Description
7. The LCD’s first pin and fifth pins are connected to the ground. 2nd
pin is connected to Vcc. 3rd pin is connected to the potentiometer
which is used to adjust the brightness of the LCD display.
The LCD’s fourth pin is connected to the Arduino’s third digital
pin. 6th pin connected to 4rth digital pin. And the LCD’s 11, 12, 13,
14 pins are connected to Arduino’s digital pins 5, 6, 7, 8
respectively.
The analog pin A1 is connected to the LM35 sensor. The pin A2 is
connected to the buzzer. And A3 pin is connected to motor.
Continued…
8. • The Arduino is programmed such that first it will check the sensor, LED’s, and the buzzer.
• After LM35 IC will detect the room temperature and the corresponding output will be
displayed in the LCD screen.
• The LED’s are connected such that,
LED – 1 0-5 Deg Celsius
LED – 2 5-10 Deg Celsius
LED – 3 10-25 Deg Celsius
LED – 4 25-35 Deg Celsius
LED – 5 35-100 Deg Celsius
According to the temperature the corresponding will glow. If the temperature is above 35 the
buzzer will let us know that the temperature exceeds the normal level. And the DC fan will be
turned on to cool down the environment.
WORKING
9. We can place water rotator or CO2 cylinder to eliminate the fire if
the temperature is crossed a particular level.
In industries these type of circuits can be used to collect the data
and also used to monitor the environment regularly with simple
equipment.
This temperature detector can be used to measure the temperature
of motor windings, measuring the temperature in bearings,
temperature of engine oil.
APPLICATION