In this paper we have discussed a various protective schemes with testing electromechanical relay. Through this practical set-up, the students can get familiar with the fundamentals of protection and can learn how different protection schemes are wired and how they. Power System Protective Relays: Principles & Practices Protective Relays - Technical Seminar Nov 2016 - Copyright: IEEE 1 Power System Protective Relays: Principles & Practices Presenter: Rasheek Rifaat, P. They play a key role in power system protection. In ETAP relay which operates when the load tantaneous over current (IOC) and 51 for a time over. several times greater than maximum load current. Each experiment details objectives, required apparatus, theoretical background, and results, providing a. Abstract: The protective systems are essential for the Protection of Power distribution and Radial Feeder System.