Introduction: Arduino Light Intensity Lamp

The purpose of this project is to create a circuit that turns on at night. This circuit is great for companies, businesses and stores because, at night, the light bulbs will turn on itself and reduce the stress and responsibility for the coworkers to turn on and off the lights every day.


  • LDR ( to detect the light/dark conditions)
  • Arduino microcontroller
  • Lightbulb
  • Relay (since the lightbulb takes 120 V and the Arduino only provides 5V)
  • Power Source
  • Bread Board
  • Resister

Step 1: Get Your Supplies Ready Around the Bread Board

Keeping your supplies gathered will save time and make the project more efficient.

Step 2: Organize Your Supplies in the Breadboard.

Make sure to change up the settings in your breadboard to make the circuit work depending on your power source.

Step 3: Connect the Wires to the Circuit.

Make sure to connect all the wires effectively and use some kind of colour to define each wire so it all becomes clear to understand for you and others.

Before doing something, link the Arduino's 5V power to the Arduino power rail and the Arduino ground into the ground line. Then attach the positive end of the power supply to the light bulb at Terminal 2. Take the ground end of the power supply and link to the relay's terminal 1. Connect the Light Bulb's ground end and Connect it to relay Terminal 7. Make sure Terminal 8 is connected to the ground train. Then attach the Relays Terminal 5 to some Wireless Pins.

Step 4: Create a Text Code for the Circuit to Work.

Create a code that will make the resistance in the bulb higher if the brightness is high so the bulb does not glow and make the resistance low when there is no brightness so the bulb glows.

Step 5: Finished!