46 C.F.R. § 120.378 Ungrounded systems.
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Each ungrounded system must be provided with a suitably sensitive ground detection system, located at the respective switchboard, that provides continuous indication of circuit status to ground with a provision to momentarily remove the indicating device from the reference ground. [CGD 85–080, 62 FR 51352, Sept. 30, 1997]
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PART 120—ELECTRICAL INSTALLATION
Subpart C—Power Sources and Distribution Systems
§ 120.378 Ungrounded systems.

