Protection of Alternators: The generating units, especially the larger ones, are relatively few in number and higher in individual cost than most other equipment's. Therefore, it is desirable and necessary…
Translay System: This system is the modified form of voltage-balance system. Although the principle of balanced (opposed) voltages is retained, it differs from the above voltage-balance system in that the…
Differential Relay: Most of the relays discussed so far relied on excess of current for their operation. Such relays are less sensitive because they cannot make correct distinction between heavy…
Definite Distance Type Impedance Relay: Fig. 21.21 shows the schematic arrangement of a Definite Distance Type Impedance Relay. It consists of a pivoted beam F and two electromagnets energized respectively…
Distance Relays or Impedance Relays: The operation of the relays discussed so far depended upon the magnitude of current or power in the protected circuit. However, there is another group…
Induction Type Directional Overcurrent Relay: The directional power relay is unsuitable for use as a directional protective relay under short-circuit conditions. When a short-circuit occurs, the system voltage falls to…
Induction Type Directional Power Relay: This Induction Type Directional Power Relay operates when power in the circuit flows in a specific direction Unlike a non-directional overcurrent relay, a directional power…
Induction Type Overcurrent Relay(Non-Directional): This Induction Type Overcurrent Relay works on the induction principle and initiates corrective measures when current in the circuit exceeds the predetermined value. The actuating source…