Design, Development and Simulation of a Microcontroller Based Automatic Electrical Mains Changeover System

Abstract

Design, development and simulation of an automatic Electrical Mains Changeover System (EMCS) using PIC microcontroller (μC) has been presented in this study. The system consists of 18-pin DIP package enhanced flash microcontroller PIC16F84A with 4 MHz crystal used as main processor, two switching transistors, two relays and Low Voltage Power Supply (LVPS). The electrical mains control signal output at RB0 and RB2 of PortB actuate two switching transistors which drive two relays to operate the loads depending on the availability of mains or backup power source. An assembly language program based on MPLAB IDE has been developed to control the operation of the system. The design and verification of the PIC μC based EMCS in Proteus 7.7 simulation platform has been completed successfully.