Directional Earth Fault Relay: In the case of Directional Earth Fault Relay the angular relationship of residual current and residual voltage is independent of the faulted phase and is governed…
Overcurrent Earth Fault Protection: Overcurrent Earth Fault Protection - Earth-fault protection can be provided with normal overcurrent relays, if the minimum earth-fault current is sufficient in magnitude. The magnitude of…
Overcurrent Protection of Feeders: Overcurrent relays offer the cheapest and the simplest protection for lines. The maximum load currents must be known to determine whether the ratio of the minimum…
Differential Relay Application: The principle of operation depends on a simple circulating current principle where the difference of the currents of the two CTs flows through the relay under normal…
Distance Relays Types and their Applications: In applying relays to a transmission system it is necessary to state the relay characteristic in the same terms that the system conditions are…
Directional Relays: Selective protection cannot be achieved with time graded overcurrent protection systems in ring or loop systems as well as in radial circuits with two end power supply. A…
Instantaneous Overcurrent Relays: If the relay operates instantly without any intentional time delay, this characteristic can generally be satisfied by a relay of the non-polarized attracted armature type. This relay…
Overcurrent Relay Characteristics: The operating time of all Overcurrent Relay Characteristics tends to become asymptotic to a definite minimum value with increase in the value of current. This is inherent…