Question 399Electricity & Electronics - Assistant Engineer

70% to pass

Referring to the containership one-line distribution diagram shown in the illustration, what is the purpose of the feedback circuit breaker as used to bypass the automatic bus transfer device? Illustration EL-0014

Diagram for USCG Electrical Assistant: Referring to the containership one-line distribution diagram shown in the...
ASince it is normally closed, it is the means by which the emergency generator control circuit senses the voltage at the main bus.
BSince it is normally closed, it is the means by which the emergency generator control circuit senses the voltage at the emergency bus.
CIt allows the emergency generator to feed the main bus during dead ship start-up; otherwise it is generally open and not used.
DIt allows the emergency generator to be paralleled with the ship's service generators when additional power is needed.
AI Explanation

The correct answer is C) It allows the emergency generator to feed the main bus during dead ship start-up; otherwise it is generally open and not used. The feedback circuit breaker is used to bypass the automatic bus transfer device, which is normally used to transfer the ship's main electrical load from the main service generators to the emergency generator when the main power source is lost. During a dead ship start-up, where the main generators are not running, the feedback circuit breaker allows the emergency generator to directly supply power to the main bus, bypassing the automatic transfer mechanism. This ensures the main bus is energized to start up the ship's systems. Otherwise, the feedback circuit breaker is typically left open and not used during normal operations. The other answer choices are incorrect because they do not accurately describe the purpose of the feedback circuit breaker in this specific electrical distribution diagram.

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