Scope

The requirements of these Rules are applicable to vessels with arrangements, equipment and systems necessary for direct current grid distribution and use of inverted a.c. electrical power by essential and emergency services through a rectified d.c. bus. The Chapter details the requirements for sub-systems and equipment for design, installation and operation of the electrical distribution systems and electrical equipment of constant voltage distribution systems. Constant current distribution systems will be subject to special consideration and are not covered by these Rules.

Where reference is made to a distribution bus, this may be effected by either bus trunking or cabling and may have connection points at locations remote from the generation and may be situated throughout the ship as opposed to conventional switchboard based tree distribution.

For merchant ships the flag Administration may impose requirements additional to those in this Chapter. Similarly, the Naval Administration may impose additional requirements for naval ships.

The following Sections state the requirements for the vessel’s electrical grid distribution systems and equipment, and are in addition to the applicable requirements of the Rules and Regulations for the Classification of Ships (hereinafter referred to as the Rules for Ships).