automatic light control at night ppt by Shubhan raj

1. Presentation on
Automatic Light
control at Night
College of Engineering Science
& Technology, Lucknow
Submitted To:-
Electrical & Electronics
Department
Submitted By:-
Shubhan Raj
Karan Pratap Singh
Deepshikha Tiwari
Shikha Sharma

2. Abstract:-
 Automatic light needs no manual operation for
switching ON and OFF when there is need of light.
 In fact we can use this circuit to implement any type
of automatic night light.

3. Contents
 Introduction
 Hardware Requirement
 Block Diagram
 Circuit Diagram
 Hardware Discription
 Simulation
 PCB Layout
 Advantage
 Conclusion

4. Introduction
 Automatic light needs no manual operation for switching
ON and OFF when there is need of light.
 It detects itself whether there is need for light or not. When
darkness rises to a certain value then automatically light is
switched ON and when there is other source of light i.e.
day time, the light gets OFF.
 The sensitive of the light can be adjusted. The circuit thus
saves the electrical power as well as man power.
 The principle involves the detection of the intensity of light
with help of LDR which changes the value of resistance
across it on the basis of light.

5. Block diagram:

6. Circuit Diagram:

7. Components:
 LDR
 IC ULN2803 (Relay Driver)
 IC LM 324
 LM7805 (Voltage Regulator)
 Resistor
 Variable Resistor
 Capacitor
 Relay
 LED
 Bulb
 Connection wire
 Soldering Tools

8. LDR
 The light dependant resistor is an electronic component
whose resistance decreases with increasing light
intensity. It is also called as “Photo Resistor” or “Photo
conductor”
 The light dependant resistor uses high resistance
semiconductor material. (Cadmium Sulphide).When light
falls on such a semiconductor the bound electrons [i.e.
Valence electrons] get the light energy from the incident
photos
Description of Hardware :

9. LED
 A light-emitting diode (LED) is a semiconductor light
source. LEDs are used as indicator lamps in many
devices and are increasingly used for other lighting
 Appearing as practical electronic components early
LEDs emitted low-intensity red light, but modern
versions are available across the visible, ultraviolet,
and infrared wavelengths, with very high brightness.

10.  It is a passive component having two terminals that
are used to manage the current flow in the circuit.
 A current that flows via a resistor is directly
proportional to the voltage that appeared into
resistor.
 Two types:
(1) Fixed value resistor
(2) Variable resistor
Resistor:

11. Relay Driver
 The eight NPN Darlington connected transistors in this family of
arrays are ideally suited for interfacing between low logic level
digital circuitry (such as TTL, CMOS or PMOS/NMOS) and the
higher current/voltage requirements of lamps, relays, printer
hammers or other similar loads.
 The major advantage of using this IC is that it can fulfill the
need for high voltage and high current also. This is enabled
through a low voltage and low current source to give high
voltage and high current output.

12. LM324
 LM324 is a 14pin IC consisting of four independent
operational amplifiers compensated in a single
package.
 Op-amps are high gain electronic voltage amplifier
with differential input and, usually, a single-ended
output. The output voltage is many times higher than
the voltage difference between input terminals of an
op-amp.

13. Voltage Regulator
 A voltage regulator is designed to automatically
maintain a constant voltage level
 Voltage regulator ICs are available with fixed voltage
(typically 5, 12 and 15V) or variable output voltages
 For ICs within the 78xx family, the xx is replaced with
two digits, indicating the output voltage (for example,
the 7805 has a 5 volt output, while the 7812
produces 12 volts)

14. Relay
 Relays are electromechanical switches.
 Relays have two circuits: A control circuit (shown in
GREEN) and a load circuit (shown in RED).
 The control circuit has small control coil while the
load circuit has a switch. The coil controls the
operation of the switch.

15. Capacitor
 To store electricity, or electrical energy.
 Also functions as filter, passing AC, and blocking
DC.
 Apply DC voltage- electric charge is stored on each
electrode.
 Three types of capacitor i.e. ceramic capacitor &
electrolytic capacitor and variable.
 Variable capacitors.

16. Simulation (using Proteus):

17. PCB Layout

18. Advantages:
 No man power required.
 Less Consumption of electrical energy.
 Less maintenance.
 Cheap and economical.
Disadvantage:-
In Sunny and rainy days, on and off time differ
notice.

19. Conclusion:
 In coming days, this will prove a great boon
to the world, since it will save a lot of
electricity of power plants that gets wasted in
illuminating the street lights. As the
conventional sources are depleting very fast,
then it`s time to think of alternatives.

20. Future Scope:-
 We can implement this project for street
lamp and also for night lamp of the room.