A reliable three-phase power supply is critical for industrial, commercial, and residential applications. However, issues such as phase loss, imbalance, undervoltage, overvoltage, and power theft can cause equipment damageanddowntime. This paper surveys IoTbased three-phase power monitoring systems that provide real-time fault detectionandSMS alerts for reporting and load protection. Typical architectures use an Arduino or ESP32 microcontroller withvoltageand current sensors to monitor the R, Y, and B phases. When a fault is detected, the controller isolates the load viarelays, triggers an alarm, and sends SMS alerts to the concerned authority. For enhanced monitoring, systems often integrateWi-Fi/GSM communication, enabling remote access to voltage, current, and load conditions through IoT platforms withgraphical visualization and data logging. Some implementations support automatic load transfer to healthy phasesandoptional GPS-based fault localization to minimize response time. The surveyed solutions improve reliability, reducedowntime, and offer cost-effective approaches suitable for smart grids, substations, factories, and residential complexes. Keywords: IoT, Arduino, Three-Phase Power System, Fault Detection, GSM Module, Voltage Sensor, Current Sensor, SMSAlerts