(This foreword is not part of ANSI C37.17-1997.)
This standard supersedes and updates the 1979 edition and all previous revised editions of the original standard published in 1956, all written by the National Electrical Manufacturers Association.
This standard pertains to direct-acting over current, reverse-current, and undervoltage trip devices of both the electromechanical and electronic types integral with low-voltage AC and general purpose DC circuit breakers covered by American National Standards.
Requirements and references for electro-mechanical devices are included for historical continuity.
This standard does not apply to molded case circuit breakers.
Suggestions for the improvement of this standard will be welcome. They should be sent to the Vice President, Engineering Department, National Electrical Manufacturers Association, 1300 North 17th Street, Suite 1847, Rosslyn, VA 22209.
This standard pertains to:
1) direct-acting overcurrent electro-mechanical trip devices
2) direct-acting overcurrent electronic trip devices
3) reverse-current trip devices
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.