Design and Implementation of a Microcontroller-Based Automatic Transfer Switch with an Overload Protection

  • Jamiu Babatunde Oyetola


Unreliability in electric power supply has elicited the proliferation of alternative power sources particularly in developing countries. However, the manual strategies and equipment employed to affect power supply switching remain fraught with various challenges. This paper presents a microcontroller based automatic transfer switch with an overload protection. The method employed in the design involves AC voltage sensor, power supply unit, PIC microcontroller, the relay driver circuit, electromechanical relays, overload protection unit, and LCD display to display the present state of the power source. The automatic transfer switch also consists of an alarm system for indicating generator failure or fuel outage. The result of the automatic transfer switch demonstrates its ability to perform transfer switching activities easily with little or no human intervention and isolated the output in case of an overload condition.Keywords: PIC microcontroller, contactor, electricity, overload