Cơ bản về bảo vệ hệ thống điện Protection system is a complete arrangement of protection equipment and other devices required to achieve a specified function based on a protection principal. Protection equipment is a collection of protection device ( relay, fuse, etc.) excluded are device such as CT’s, CB’s, contactor, etc. Protection scheme is a collection of protection equipment providing a defined function and including all equipment required to make the scheme work (i.e. relays, CT’s, CB’s Batteries, etc.)