This SAE Definition Document contains historic voltage regulation methods and test requirements that have not been previously published. The purpose of this document is to recommend a set of definitions and practices for use on current and future 12 V vehicle electric power regulation and control systems in internal combustion engine road vehicles. This document is not intended to include nor exclude regulators used in higher voltage vehicle electrical systems. The term “generator” rather than “alternator” will be used even though these terms may be used interchangeably in practice.
This SAE Recommended Practice is intended to apply to lamps, batteries, heaters, radios, and similar equipment for operation with mobile or automotive diesel engines. Twenty-four V systems have long been used for heavy-duty services because 24 V permit operating 12 V systems in series-parallel. Thirty-two V systems have been used for marine, railroad-car lighting, and other uses. Generators, storage batteries, starting motors, lighting, and auxiliary electrical equipment shall be for nominal system ratings of 12, 24, or 32 V as determined by the power requirements of the application. It is recommended that no intermediate voltages be considered. The combination of a 24 V starting motor and two 12 V batteries connected in series for cranking is considered practical where it can be adapted to the installation.
a) Creation of a standard specific to integration of energy storage systems into electrification of buses of all types which comprehends safety, performance, life and cost considerations utilizing worldwide standards as references in order to maximize existing work. The document applies to both purpose built electric buses and retrofit electrified buses. b) Harmonization of these existing standards achieve specific objectives that provide guidance in effective and safe designs of electrificed buses which utilize battery pack systems as the energy storage device. c) Future Considerations