VoltSentry — Relay Overvoltage Protection System

About this project

VoltSentry is a relay-based overvoltage protection system built on Arduino Uno that monitors an incoming DC voltage and automatically disconnects a load when the voltage exceeds a user-set trip threshold. A potentiometer simulates a variable DC bus (0–25 V), a 5 V relay module controls the load circuit, and a 16×2 I2C LCD displays live voltage, trip setpoint, and protection state. Three status LEDs (green/yellow/red) and an active buzzer provide immediate visual and audio feedback. The system implements 1 V hysteresis to prevent contact chatter, adjustable trip setpoint via UP/DOWN buttons, and a manual RESET button with a voltage-safe interlock — exactly the functional elements found in industrial overvoltage protection relays.

What you get

• Complete, commented source code
• Full components list with quantities
• Pin-by-pin wiring guide and connection table
• Step-by-step upload and testing guide
• Project report (.docx, IEEE style)
• Presentation slides (.pptx)