USCG Exam PracticeSwitchboards and distribution systems
According to 46 CFR §111.30-29, which instrument must be fitted at an AC emergency switchboard to allow the operator to monitor current on each phase?
- A. A wattmeter with a phase selector switch
- B. A power-factor meter connected to each phase
- ✓ An ammeter with a selector switch that connects to each phaseCorrect
- D. A synchroscope connected between the generator and the bus
Why C is correct
46 CFR §111.30-29(f)(1) requires each AC emergency switchboard to have an ammeter with a selector switch that connects the ammeter to show the current for each phase. A wattmeter and synchroscope are not listed as required instruments for the emergency switchboard in this section.
Cited:46 CFR §111.30-29