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)…
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…
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…
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…
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…
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…
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…
Electromagnetic Relay - Definition, Construction and Working Principle: Electromagnetic Relay - A relay, in the general sense of the word, is any apparatus which serves to actuate or control the…