Question 188Electricity & Electronics - QMED

The correct answer is D) higher than the bus frequency. When synchronizing two AC generators, the synchroscope pointer revolving in the fast direction indicates that the frequency of the oncoming generator is higher than the bus frequency. This is because the higher frequency generator is running ahead of the bus frequency, causing the synchroscope pointer to rotate in the fast direction. The other options are incorrect because A) the frequencies must match for the circuit breaker to be closed, C) the frequencies must match in both frequency and phase for the circuit breaker to be closed, and B) a lower frequency oncoming generator would cause the synchroscope pointer to rotate in the slower direction.