Question 505Electricity/Electronics - Assistant Engineer70% to pass
As shown in the illustrated one-line diagram of a two-tiered emergency power system for a passenger ship, what statement is true? Illustration EL-0166
AI Explanation
The correct answer is A.
On a loss of normal ship's power, the temporary emergency loads power source is the battery (from AC/DC UPS "B"), whereas the final emergency loads power source is the emergency generator. This is in accordance with maritime regulations that require emergency power systems to have a temporary source (such as batteries) to immediately supply critical loads, followed by a final source (such as an emergency generator) to sustain power for a longer duration.
The other options are incorrect because they do not accurately describe the power flow and sources as depicted in the one-line diagram. For example, option B incorrectly states that the final emergency loads power source is the battery, when it should be the emergency generator.
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