Equipment Protection: Preserves transformers, generators, motors, and other critical assets from fault damage. Based on Operating Principle Electromechanical Relays: Work using moving parts and electromagnetic forces (traditional relays). Static Relays: Use electronic components without moving parts. Selectivity is a mandatory requirement for all protection, but the importance of it depends on the application. Types of Protective Relays: Protective relays are categorized by their mechanism (electromagnetic, static, mechanical) and function. Protective relays and devices have been developed over 100 years ago to provide “last line” of defense for the electrical systems. The applications of the different types of protection systems for the protection of various types of equipment and transmission lines are.
