Automatic battery charger
Automatic battery charger
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💡 DIY Auto On/Off Light Sensor – Save Power Automatically!
💡 DIY Auto On/Off Light Sensor – Save Power Automatically! Controlling lights automatically using a light sensor is a smart way to save electricity , improve convenience , and extend bulb life . In this post, you’ll learn how an Auto On/Off Light Sensor works and how to make one at home. 🔍 What Is an Auto On/Off Light Sensor? It’s a simple circuit or device that turns lights ON at night and OFF during the day using a LDR (Light Dependent Resistor) or a photodiode sensor . Common names: Day/Night Switch Automatic Street Light Controller Light-activated switch 🧪 Components Required Component Quantity Description LDR (Light Sensor) 1 Detects ambient light NPN Transistor (e.g., BC547) 1 Acts as a switch Relay Module (5V) 1 Controls AC load (bulb/fan) Resistor (10kΩ, 1kΩ) 2 For biasing Power Source (5V–12V) 1 Battery or adapter LED or AC Bulb 1 For output control Connecting wires - For connections ⚙️ Working Principle The LDR changes resistance based on...