Operating Principles and Relay Construction: Electromagnetic relays, thermal relays, static relays, microprocessor based protective relaysOperating Principles and Relay Construction: Electromagnetic relays, thermal relays, static relays, microprocessor based protective relaysProtective relays and devices have been developed over 100 years ago to provide “last line” of defense for the electrical systems. 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. 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. To introduce all kinds of circuit breakers and relays for protection of Generators, Transformers and feeder bus bars from Over voltages and other hazards. To describe neutral grounding for overall protection. Sequence Components and Fault Analysis: sequence impedance, fault calculations, Single line to ground fault, Line to ground fault with Zf, Faults in Power syst ional relays, Distance relays, Differential relays. Based on Operating Principle Electromechanical Relays: Work using moving parts and electromagnetic forces (traditional relays). Static Relays: Use electronic components without moving parts.
