Smart Lights

Introduction: Smart Lights


Objective:- In this project, I am going to show you how to control the intensity of LED lights according to the light intensity of outer atmosphere. This is an amazing and very useful project because it prevents the wastage of electricity.

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Step 1: Materials Required

Materials required:


Arduino Uno

LDR Sensor

Jumper wires

Arduino Software

Step 2: Working


In the circuit a LDR (Light Dependent Resistor) is used, which detect the intensity of the lights, when the intensity of light comes under a fixed values the led Light is turn ON.We can utilize the light sensor circuit for automatic switching of the loads based on daylight’s intensity by using a light sensor.It works on the phenomenon of Photoconductivity is an optical and electrical phenomenon in which a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, ultraviolet light, infrared light, or gamma radiation.

What is Sensor?

Sensor is a device that is used to detect the changes in quantities or events and appropriately produce the outputs.LDR (Light Dependent Resistor or photoresistor) is used as a light sensor in this light sensor circuit. These LDR sensors are passive and doesn’t produce any electrical energy.

The light sensor circuit is an electronic circuit designed using (light sensor) LDR, Darlington pair, relay, diode, and resistors which are connected as shown in the light sensor circuit diagram which is already created.

During the daytime, the light sensor LDR has very-low resistance of around a few 100Ω. Thus, the supply passes through the LDR and ground through the resistor and variable resistor as shown in the light sensor circuit. It remains LOW.At night it becomes High. We have to code like that.

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    2 Discussions

    Nice project. Do you have any more pictures of the setup.


    Reply 1 year ago

    Thanks for the feedback.

    I will be uploading the same in the same soon with some improvements.

    Please have a look and share your feedback