Design, construction and calibration of automatic street light controller using Light Dependent Resistor (LDR)

E.o Echeweozo ,N.O Okoro,P Ngele

doi:10.4314/jasem.v23i3.14

Abstract

Automatic street light power saving system using the Light Dependent Resistor (LDR) is a simple and powerful concept, to switch ON/OFF the street light system automatically. It automatically switches ON the streetlight when the sunlight goes below the visible region of our eyes and switches OFF the streetlight when ample amount of sunlight is available. From this work, it was observed that the implementation of LDR in streetlight circuit design would reduce the running cost of street lightning system by 51.7%. Keywords: Streetlight, Energy, Light, Dependent, Resistor

Highlights

10 AC supplyBefore mounting any component in the circuit it is a good practice to check whether a component works properly or not so that time consumption in troubleshooting can be avoided
Street lighting provides a safe night time environment for all road users including pedestrians
LDR (Light Dependent Resistor) is a device whose sensitivity depends upon the intensity of light falling on it

Summary

10 AC supply

Before mounting any component in the circuit it is a good practice to check whether a component works properly or not so that time consumption in troubleshooting can be avoided. Cover LDR properly so that no light beam fall in it, again measure the resistance it must be high. Whenever light falls over LDR its resistance get decreased and transistor Q1 turns ON while the collector current of this transistor goes LOW, and this makes the second transistor turns OFF due to getting a LOW signal at its base, the transistor will be in cut-off region the relay will not be energized, the AC load remains in the OFF state. Due to a LOW signal at the Q1 base, Q2 transistor gets a HIGH signal from the collector of Q1 and energizes the Relay which turns ON the AC load that is connected to it. In order to calculate the electrical energy used and saved in this work the formula below would be used

AND DISCUSSION

Conclusion