This presentation reviews the established principles and the advanced aspects of the selection and application of protective relays in the overall protection system, multifunctional numerical devices application for power distribution and industrial systems, and addresses some. This presentation reviews the established principles and the advanced aspects of the selection and application of protective relays in the overall protection system, multifunctional numerical devices application for power distribution and industrial systems, and addresses some. Experience the benchmark in grid protection, automation, and monitoring! SIPROTEC 5, built on extensive field experience, offers comprehensive functionalities and device types for modern electrical energy systems. Its modular design and powerful DIGSI 5 engineering tool provide tailored solutions. They are intended to quickly identify a fault and isolate it so the balance of the system continue to run under normal conditions. The selection and applications of. ABB introduces a new all-in-one protection relay for power generation and distribution applications to ensure maximum flexibility and cost-effectiveness throughout the relay life cycle. The new, freely configurable all-in-one protection and control relay REX615 is a technological leap forward from. We are happy to introduce the next step for the 615 and 620 series relays, REX615 – the latest addition to the Relion® family of relays. With more than 1 million relays installed worldwide, the 615 and 620 series have been the choice of many over the years, demonstrating reliability and commitment. Engineering use: Relays are used on feeders, transformers, buses, motors, generators, and transmission lines to protect equipment and improve system reliability. What controls it: Relay performance depends on the protected zone, CT/PT inputs, pickup settings, time delay, breaker clearing time, trip. SEL relays detect faults and other abnormal conditions in electric power systems and initiate protective actions to maintain system stability and safety.