Design and implementation of a low-cost Arduino-based three-phase electrical monitoring and reporting system

Three-phase electrical systems are extensively adopted in industrial, commercial, and institutional environments due to their high efficiency and ability to support heavy electrical loads. Continuous and real-time monitoring of these systems remains a significant challenge, particularly in developing regions, small-scale industries, and educational laboratories. Traditional monitoring approaches are largely manual and reactive, making them ineffective at detecting transient faults such as voltage imbalance, phase failure, and overcurrent at an early stage. This study presents the design and implementation of a low-cost, Arduino-based three-phase electrical monitoring and reporting system capable of real-time data acquisition, fault detection, and remote user notification. The system integrates ZMPT101B voltage sensors and ACS712 current sensors with an Arduino Mega 2560 microcontroller to measure key electrical parameters RMS voltage, RMS current, active power, apparent power, and power factor across all three phases. Processed data is displayed locally on a 20×4 I2C LCD and transmitted remotely via a SIM900/SIM800L GSM module through SMS alerts. Experimental testing validated the system's performance, recording voltage measurement errors of less than 0.4% and current errors of approximately 1.5%. The fault detection module successfully identified all simulated anomalies including over-voltage, under-voltage, phase imbalance, and phase failure within 500 milliseconds, achieving a 100% local detection rate. The GSM reporting subsystem attained an overall SMS delivery success rate of 98% with an average latency of 5.8 seconds. These results demonstrate that the proposed system provides a practical, reliable, and cost-effective alternative to expensive commercial power analyzers, making it well-suited for educational institutions, workshops, and small-scale industries.