Marine Electrical Systems USCG Q#486 (Set 17)

In the illustration shown, what would be the functional name for the coil represented as '1S'? Illustration EL-0012

USCG Exam Illustration EL-0012
USCG Examination Diagram: Illustration EL-0012
Official USCG Answer & Rule Citation

Correct Answer: Option A — neutral contactor coil (for autotransformer wye connection)

In marine autotransformer motor starters, designated coil '1S' closes the wye-connection to establish the initial reduced-voltage starting step before transitioning to the running configuration per IEEE 45 standards.

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