{"data":{"id":"us/46-cfr-111.30-27","jurisdiction":"us","citation":"46 CFR 111.30-27","heading":"-27 Direct current ship's service switchboards.","body":"(a) Each direct current ship's service switchboard must have the equipment required by paragraphs (b) through (f) of this section.\n(b) For each connected generator, each switchboard must have the following:\n(1) A circuit breaker that meets § 111.12-11 and § 111.50-5.\n(2) A disconnect switch or link for each generator conductor, except a switchboard having a draw-out or plug-in type generator circuit breaker that disconnects—\n(i) Each conductor; or\n(ii) If there is a switch in the generator neutral, each ungrounded conductor.\n(3) A field rheostat.\n(4) An indicator light connected between the generator and circuit breaker.\n(c) For each two-wire generator, each switchboard must have:\n(1) An ammeter; and\n(2) A voltmeter with a selector switch that connects the voltmeter to show:\n(i) Generator voltage; and\n(ii) Bus voltage.\n(d) For each three-wire generator, each switchboard must have the following:\n(1) An ammeter for:\n(i) The positive lead; and\n(ii) The negative lead.\n(2) A center zero type ammeter for the neutral ground connection.\n(3) A voltmeter with a selector switch that connects the voltmeter to show generator and bus voltage:\n(i) Positive to negative;\n(ii) Positive to neutral; and\n(iii) Neutral to negative.\n(e) Each switchboard must have ground detection that meets subpart 111.05 for the:\n(1) Main power system;\n(2) Main lighting system; and\n(3) Emergency lighting system.\n(f) For each shore power connection, each switchboard must have:\n(1) A circuit breaker or fused switch; and\n(2) A pilot light connected to the shore side.\n(g) One of the voltmeters under paragraph (c)(2) or (d)(3) of this section must be connected to show:\n(1) For each two-wire system, shore connection voltage; and\n(2) For each three-wire system, shore connection voltage:\n(i) Positive to negative;\n(ii) Positive to neutral; and\n(iii) Neutral to negative.","path":["Title 46—Shipping","CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY","SUBCHAPTER J—ELECTRICAL ENGINEERING","PART 111—ELECTRIC SYSTEMS—GENERAL REQUIREMENTS","Subpart 111.30—Switchboards"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-46.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:22Z","sha256":"aac70f2f03892a142560988dbddf799d3742b7fc4fed0185345878cc987895f7","source_id":"us-cfr","stale":true,"prev":"us/46-cfr-111.30-25","next":"us/46-cfr-111.30-29"},"notice":"GroundRules: Original legal text. Not legal advice."}