(i) Pick-up current - It is the minimum current in the relay coil at which the relay starts to operate when the current in the relay is less than the pick-up value there lay does not operate and the breaker controlled by it remains in the closed position. When the relay coil current is equal to or greater than the pickup value, the relay operates to energies the trip Coil that opens the circuit breaker. (ii) Current setting – It is often desirable to adjust the pickup current to any value. This is know as current setting and is usually achieved by the use of tapping on the relay coil. The taps are brought out to a plug bridge, which permits to alter the number of turns on the relay coil, this changes the torque on the disc and the hence the time of operation of the relay. Pickup read more

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