USCG Exam PracticeMotor controllers and remote control
Under 46 CFR §111.70-1, the motor disconnecting means on a vessel must be which of the following?
- ✓ An externally operable switch or circuit breakerCorrect
- B. An internally operable fused disconnect accessible only with a tool
- C. A thermal overload relay mounted within the controller enclosure
- D. A remote-operated contactor controlled from the engine room console
Why A is correct
46 CFR §111.70-1(c) states explicitly that the motor disconnecting means must be an externally operable switch or circuit breaker. Internal or tool-only access devices and contactors do not satisfy this requirement.
Cited:46 CFR §111.70-1