These devices provide measurement, control, and relay protection for the 10 kV switchgear. This guide represents a short overview of fundamentals of a power system protection, operating principles and relay characteristics as well as description of main switchgear components like various types of circuit breakers, CTs and PTs, relays etc. It is customary to have two elements of. Electrical switchgear protection fundamentally involves the integrated deployment of equipment, primarily protective relays, circuit breakers, and fuses, to actively safeguard an entire electrical system by isolating and meticulously controlling power flow.