Education 25.13 Auxiliary and lockout (86) relays adminFeb 3, 2020 An important type of “accessory” relay, especially for legacy electromechanical protective relays, is the...
Education 25.12 Distance (21) protection adminFeb 3, 2020 A form of protection against faults on long-distance power lines is called distance relaying, so named...
Education 25.11 Directional overcurrent (67) protection adminFeb 3, 2020 While 50 and 51 (instantaneous and time overcurrent) relay functions monitor line current magnitude and guard against...
Education 25.10 Differential (87) current protection adminFeb 3, 2020 One of the fundamental laws of electric circuits is Kirchhoff’s Current Law, which states the algebraic sum of...
Education 25.9 Instantaneous and time-overcurrent (50/51) protection adminFeb 3, 2020 Perhaps the most basic and necessary protective relay function is overcurrent: commanding a circuit breaker to...
Education 25.8 ANSI/IEEE function number codes adminFeb 3, 2020 In the United States, the ANSI and IEEE organizations have standardized a set of numerical codes referring to...
Education 25.7 Introduction to protective relaying adminFeb 3, 2020 Circuit breakers used in residential, commercial, and light industrial service are self-tripping devices: they...
Education 25.6 Electrical Sensors: Potential Transformers (PTs) and Current Transformers (CTs) adminFeb 3, 2020 The two “process variables” we rely on most heavily in the field of electrical measurement and control...
General 25.5 Circuit breakers and disconnects adminFeb 3, 2020 Circuit breakers are the “final control elements” of the electric power industry, akin to control valves in...
Education 25.4 Single-line electrical diagrams adminFeb 3, 2020 Electrical power grids primarily consist of three-phase AC circuits. This means most power lines...
Education 25.3 Interconnected generators adminFeb 3, 2020 Any power grid large enough to meet the demand of an entire nation must have multiple generators drawing from multiple...
Education 25.2 Understanding Electrical Power Grids adminFeb 3, 2020 The term “grid” refers to the conductors and equipment interconnecting power sources to power loads in a...
Education Chapter 25 Electric Power Measurement and Control Systems adminFeb 3, 2020 Electrical power is a commodity in the modern world, bought and sold on the open market like any other. Thus, it is...