Question 108Electricity/Electronics - 1st Asst/Chief70% to pass
In preparation for paralleling generators, if the electric plant condition is as shown by graph "A", what would be the rotational status of the synchronizing lamps as shown in circuit "B"? Illustration EL-0002
AI Explanation
The correct answer is B) Revolve slowly in the fast direction.
When the electric plant condition is as shown by graph "A", it indicates that the generator being paralleled is running at a slightly higher frequency than the running generator. In this scenario, the synchronizing lamps in circuit "B" will revolve slowly in the fast direction, indicating that the generator speeds need to be adjusted to match for a successful parallel.
The other options are incorrect because: A) The lamps would revolve slowly in the slow direction if the generator being paralleled was running at a lower frequency. C) The lamps would revolve rapidly in the slow direction if the generator being paralleled was running at a significantly lower frequency. D) The lamps would not remain stationary, as this would indicate that the generator speeds are perfectly matched, which is not the case in the given scenario.
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