Induction Type Negative Phase Sequence Relay: This type of induction type negative phase sequence relay has similar construction as that of an induction type overcurrent relay. The difference lies only in the primary winding provided…
Negative Phase Sequence Relay: A negative phase sequence relay (or phase unbalance) is essentially provided for the protection of generators and motors against unbalanced loading that may arise due to phase-to-phase faults. Essentially such a…
Voltage Balance Differential Relay: In this voltage balance differential relay arrangement, two similar current transformers are connected at either end of the system element under protection (such as a feeder) by means of pilot wires.…
Mho Type Distance Relay - Working and Characteristics: Mho relay is a high speed relay and is also known as admittance relay. It is also sometimes called an angle impedance relay. In this Mho type…
Universal Relay Torque Equation Derivation: Universal Relay Torque Equation - Most of the protection relays consist of some arrangement of electromagnets. These electromagnets have either current windings or voltage windings and in some cases both…
Thermal Relay Construction and Working Principle: Thermal Relay can operate on the principle of thermal effect of electric current. It consists of bimetallic strips which are used in small sizes and are heated by heating…
Permanent Magnet Moving Coil Relay: The arrangement of permanent magnet moving coil relay is shown in Fig. 9.12. In this relay, the coil is free to rotate in the magnetic field of a permanent magnet.…
Electromagnetic Induction Relay - Structure and Working Principle: Electromagnetic induction relay operate on the principle of induction motor and are widely used for protective relaying purposes involving a.c. quantities. They are not used with d.c.…
Classification of Relays: The protective relay may be defined as an electrical device interposed between the main circuit and the circuit breaker in such a manner that any abnormality in the circuit acts on the…
Types of Circuit Breaker Mounting: There are four types of circuit breaker mounting, which are described below: Cubicle Type or Cellular Type: In this type of mountings the circuit breakers and their ancillary equipment are…