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Distance relay

 Distance relay is used for the protection of transmission line & feeders In a distance relay, instead of comparing the…

Directional Over Current Relays

 1.                          When fault current can flow in both the directions through the relay, at its location. Therefore, it is necessary to…

Definition of Torque

Torque is defined as the moment of the external applied force about a point or axis of rotation. The expression…

Impedance Relay

The torque equation T, for such a relay the current actuates the operating torque and the voltage actuates the restraining…

Electromagnetic Relay

Electromagnetic relays are those relays which are operated by electromagnetic action. Modern electrical protection relays are mainly micro processor based,…

Zones and types of Protection system

 Zones of Protection system ·         An electric power system is divided into several zones of protection. Each zone of protection, contains…

NATURE &EFFECT OF TRANSFRMER FAULTS

 A faults on transformer winding is controlled in magnitude by  a)                         Source & neutral earthing impedance  b)                         Leakage reactance of the transformer…

TRANSFORMER PROTECTION

 •                          The power transformer is one of the most important links in a power transmission and distribution system.  •                         It is a…

Nature and causes of faults