This document discusses a microcontroller-based relay system for detecting faults in a power system. It describes how the microcontroller monitors electrical parameters in real-time, detects abnormal conditions, and sends a trip signal to circuit breakers. The microcontroller converts analog signals to digital using an ADC and detects faults based on programmed conditions. It also discusses using the system to implement overvoltage/undervoltage protection and the advantages of microcontroller-based relays over electromechanical relays.