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 mounted fuse block accessible only with tools
- C. A remote-operated contactor controlled from the bridge
- D. A thermal overload relay with manual reset
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. A thermal overload relay provides running protection, not disconnection, and a fuse block or remote contactor does not satisfy the externally operable requirement.
Cited:46 CFR §111.70-1