This standard pertains to the requirements for direct acting current and voltage protective functions of: 1) direct-acting overcurrent electro-mechanical trip devices 2) direct-acting overcurrent electronic trip system 3) reverse-current trip systems 4) undervoltage trip devices that are integral with low voltage AC and DC power circuit breakers covered by ANSI/IEEE C37.13, ANSI/IEEE C37.14, and ANSI C37.16. Additional information, communication and/or additional internal or external protective functions or devices are not covered by this standard. This standard should not be interpreted to restrict the inclusion of such functionality in the device.

The purpose of this project is to bring the standard up-to-date and to correct several serious changes to the text which were made during the publishing process after the final balloting in 1996. These changes rendered the standard incomplete and inaccurate. Additionally, since the document was transferred from NEMA to IEEE in 2002, it must be brought into compliance with the formatting and titling requirements of IEEE-SA standards.