USCG Exam PracticeElectrical troubleshooting and maintenance
A feeder circuit is isolated from the main source by a transformer. Per 46 CFR §111.05-23, where must a ground indicator be provided for this circuit, and what alternative arrangement is expressly permitted?
- A. Only at the main switchboard; no alternative arrangement is permitted
- ✓ At the distribution switchboard or another location such as a centralized monitoring position; an alarm contact or indicating device returned to the main switchboard via control cable is permittedCorrect
- C. Only at the transformer secondary terminals; remote indication is not permitted
- D. At the propulsion switchboard; a local audible alarm at the transformer is the only permitted alternative
Why B is correct
46 CFR §111.05-23(d) requires a ground indicator at the distribution switchboard or at another location such as a centralized monitoring position for the circuit affected. The note to paragraph (d) expressly permits an alarm contact or indicating device returned to the main switchboard via control cable, allowing the detecting equipment to remain near the transformer for local troubleshooting.
Cited:46 CFR §111.05-23