Switchboards and distribution systems

46 CFR §111.05-17

§ 111.05-17 -17 Generation and distribution system grounding. The neutral of each grounded generation and distribution system must: (a) Be grounded at the generator switchboard, except the neutral of an emergency power generation system must be grounded with: (1) No direct ground connection at the emergency switchboard; (2) The neutral bus permanently connected to the neutral bus on the main switchboard; and (3) No switch, circuit breaker, or fuse in the neutral conductor of the bus-tie feeder connecting the emergency switchboard to the main switchboard; and (b) Have the ground connection accessible for checking the insulation resistance of the generator to ground before the generator is connected to the bus.

46 CFR §111.05-37

§ 111.05-37 -37 Overcurrent devices. (a) A permanently grounded conductor must not have an overcurrent device unless the overcurrent device simultaneously opens each ungrounded conductor of the circuit. (b) The neutral conductor of the emergency-main switchboard bus-tie must not have a switch or circuit breaker. [CGD 94-108, 61 FR 28276, June 4, 1996]

46 CFR §111.30-29

§ 111.30-29 -29 Emergency switchboards. (a) Each emergency generator must have an emergency switchboard. (b) There must be a test switch at the emergency switchboard to simulate a failure of the normal power source and cause the emergency loads to be supplied from the emergency power source. (c) The emergency switchboard must be as near as practicable to the emergency power source but not in the same space as a battery emergency power source. (d) Each switchboard of an alternating-current emergency generator must have: (1) A circuit breaker that meets § 111.12-11; (2) A disconnect switch or link for each emergency generator conductor, except for a switchboard with a draw out or plug-in type generator circuit breaker that disconnects: (i) Each generator conductor; and (ii) If there …

46 CFR §111.40-11

§ 111.40-11 -11 Numbered switching unit and panelboard directory. (a) Each panelboard switching unit must be numbered. (b) Each panelboard must have: (1) A circuit directory cardholder; and (2) A circuit directory that has: (i) The circuit designation of each circuit; (ii) A description of the load of each circuit; and (iii) The rating or setting of the overcurrent protective device for each circuit.

46 CFR §111.95-3

§ 111.95-3 -3 General requirements. (a) Each electrical component (e.g., enclosure, motor controller, or motor) must be constructed to the appropriate NEMA or IEC degree of protection requirement for the service and environment in which it is installed. (b) Each main line emergency disconnect switch, if accessible to an unauthorized person, must have a means to lock the switch in the open-circuit position with a padlock or its equivalent. The switch must not lock in the closed-circuit position. [CGD 94-108, 61 FR 28283, June 4, 1996]

46 CFR §183.330

§ 183.330 Distribution panels and switchboards. (a) Each distribution panel and switchboard must be in as dry a location as practicable, adequately ventilated, and protected from falling debris and dripping or splashing water. (b) Each distribution panel or switchboard must be totally enclosed and of the dead front type. (c) Each switchboard must be fitted with a dripshield. (d) Distribution panels and switchboards that are accessible from the rear must be constructed to prevent a person from accidentally contacting energized parts. (e) Working space must be provided around all main distribution panels and switchboards of at least 610 millimeters (24 inches) in front of the switchboard, and at least 455 millimeters (18 inches) behind the switchboard. Rear access is prohibited when the…