Electrical systems for many types of boats are complex. U. S. Federal regulation address critical
areas pertaining to electrical systems from the standpoint of safety and stipulate requirements to
assure good practice in these areas. Some requirements may be specifically applied but many
requirements interact with others such as determination of wire size and overcurrent protection.
The large number of requirements and the possible interpretations tend to be confusing for those
using the regulations.
Regulations are typically written in concise terms, the words and arrangement chosen to be
enforceable and in some cases to be legally interpreted. This format prohibits including
explanations, recommendations and easily detected alternate solutions. A regulation provides an
outline about which a great deal of further information, interpretation, explanation, clarification
and helpful hints are needed in order to provide good understanding and compliance with its
This electrical system guideline attempts to assist the average boat builder in achieving
compliance with these regulations. It explains, diagrams, makes some recommendations and, in
general, complements the regulations to improve the boat builder's understanding.
This guideline only addresses provisions of the Federal Regulations. It is not a complete
engineering manual for the design of electrical systems on boats. There are other manuals and
standards available for this purpose such as American Boat & Yacht Council (ABYC) standards
E-2, E-4, E-10, and E-11, © 2008 American Boat & Yacht Council, Inc.