Design and Implementation of an Arduino-Based Over/Under Voltage Protection System for Domestic Applications

Abstract: Voltage instability in residential power systems poses significant risks to electrical appliances, leading to inefficiencies, safety hazards, and irreversible damage. This paper presents a low-cost, Arduino Uno-based protection system designed to monitor and mitigate overvoltage (>250V) and undervoltage (<200V) conditions in real time. The system integrates a ZMPT101B voltage sensor for precise AC voltage measurement, a 16x2 LCD for user-friendly status display, and a relay module for automated load disconnection during anomalies. Calibrated to operate within ±3% accuracy, the system processes voltage data via an ATmega328P microcontroller, triggering load isolation within 1.5–2 seconds of detecting unsafe conditions. Experimental validation under simulated voltage fluctuations (180–260V) demonstrated 98% reliability in load protection. Compared to industrial-grade solutions, this system reduces costs by 70% while maintaining robust performance, making it ideal for household applications. Future enhancements include IoT integration for remote monitoring and machine learning for predictive fault detection.