Marine Electrical Systems USCG Q#302 (Set 11)

Which electrical schematic symbol represents a normally open thermostat? Illustration EL-0059

USCG Exam Illustration EL-0059 — USCG Examination Diagram: **Illustration EL-0059**

Official USCG Answer & Rule Citation

Correct Answer: Option D — 9

Per IEEE 45 and standard electrical diagramming practices, symbol 9 designates a normally open thermostat, which closes upon sensing a specific temperature threshold to actuate control or alarm circuits in marine engineering systems.

All Marine Electrical Systems Sets Practice Set 11