Distance Relays Types

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…

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Single Phase Directional Relay

Single Phase Directional Relay: Single Phase Directional Relay - The general Eq. (4.8) suggests that for directional control the individual torques, viz. K |A|2 and K′ |B|2 should be eliminated. Considering a…

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Directional Relays

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…

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Time Current Relay Application

Time Current Relay Application: Time Current Relay Application - Overcurrent and earth fault protective gear can be made discriminative by grading the operating times of successive devices. The pickup currents…

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Instantaneous Overcurrent Relays

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…

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Overcurrent Relay Characteristics

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…

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General Equation for Electromagnetic Relay

General Equation for Electromagnetic Relay: It has already been shown that when not more than two quantities are involved, the equation for the characteristic of the relay at the threshold…

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