Question 385Electricity & Electronics - Assistant Engineer

The correct answer is A) the power flow is the same as the tripping direction. In a reverse power relay, the timer element is energized when the power flow is in the opposite direction to the normal operating condition. This is to detect situations where the power is flowing back into the generator, which could potentially damage the equipment. The relay is designed to trip and disconnect the generator when this reverse power condition is detected, and the timer element ensures there is a short delay before tripping to prevent nuisance tripping. The other answer choices are incorrect because: B) the damping mechanism is related to the speed of the relay's disk movement, not the timer energization; C) the timer is energized when the power flow is opposite to the tripping direction, not the same; and D) the generator being motorized is not relevant to the reverse power relay's timer operation.