Design of microcontroller based multi-functional relay for automated protective system

This paper presents the design and implementation of a microcontroller based multi-functional relay that can protect the equipment against over-current, over-voltage & under voltage. Provision for settings of over voltage, over current and under voltage limits is provided. Simulations are carried out using proteus eight (SP4) platforms and hardware prototype with ATMega328 as core controller is built to validate the operation of the microcontroller as multifunctional numerical relay.