Question 183Electricity/Electronics - QMED70% to pass
When paralleling two alternators, the synchronizing lamps remain lit as the synchroscope pointer approaches the 0°. What does this indicate?
AI Explanation
The correct answer is B) the synchroscope is defective or broken.
When paralleling two alternators, the synchronizing lamps should go out as the synchroscope pointer approaches the 0° position, indicating that the voltages, frequencies, and phase angles of the two alternators are properly synchronized. If the synchronizing lamps remain lit as the synchroscope pointer approaches 0°, it indicates that the synchroscope is not functioning correctly and is not accurately displaying the phase relationship between the two alternators.
The other answer choices are incorrect because: A) the alternator voltages being 180 degrees apart would cause the synchronizing lamps to remain lit, but this is not the expected behavior; C) the incoming alternator running too fast would cause the synchroscope pointer to move past the 0° position, not remain at 0°; and D) the alternator power factors being in phase would not explain the synchronizing lamps remaining lit.
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