1. Photoelectric Switch Department Of Physics Prof.Kurkute.P.V.
Radhabai Kale Mahila Mahavidyalaya,Ahmednagar.
Department Of Physics
Photoelectric Switch
Represented By
Prof.Kurkute.P.V.

2. Photoelectric Switch

3. Principle It is based on principle of light sensor.
It detect change in intensity of light and appropriately produces the output.

4. List of Components 1.IC 555 ( Timer ) 2.IC 7805 3. Transformer 4.Relay
5.LDR
6.Transistor
7.Bridge Rectifier
(Capacitor , Switch , LED, Bulb , Holder , PCB ,PBT ,Connector )

5. Sr no
Name of Component
Photo 1
LDR 2
Timer (IC 555 ) 3
Relay 4
Transformer 5
Regulator IC7805 6
Bridge Rectifier 7
Transistor 8
Resister 9
Capacitor

6. IC 555 It is also known as Timer .
In Digital system rectangular waveforms are required .
The circuit which generates rectangular waveform is called as Multivibrator circuit.
IC 555 operates both Mono stable and Astable Multivibrator .

7. Relay
Relay generally consists of a coil ,this coil gets energized whenever it gets enough supply .
Relay plays Vital role in light sensor circuit for activating the load or for connecting the load to the light sensor circuit as well as to the AC mains.

8. Block Diagram

9. Circuit Diagram .

10. Applications
It is used for power saver for street light control , system , a solar highway system with auto turn off in daytime , sunrise to sunrise lighting .
It is used for understand the logic of LDR.
It is used in camera light meters ,clocks radios ,light beams alarms.
It can be used as berglar alarm ,if bulb is replaced by buzzer.

11. Advantages 1 LDR which is cheap and consumes less energy.
2.The project works on DC low voltage .
3.The components used are cheap ,easily available .

12. Thank You