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?
- A. An internally operable fused disconnect block
- ✓ An externally operable switch or circuit breakerCorrect
- C. A thermal overload relay rated for the full motor current
- D. A manually reset pushbutton located inside the controller enclosure
Why B 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 disconnect blocks and overload relays do not satisfy this requirement.
Cited:46 CFR §111.70-1