scope:

This recommended practice provides information for selecting the proper circuit breaker for a particular application. This recommended practice helps the application engineer specify the type of circuit breaker, ratings, trip functions, accessories, acceptance tests, and maintenance requirements. It also discusses circuit breakers for special applications, e.g., instantaneous only and switches. In addition, it provides information for applying circuit breakers at different locations in the power system, and for protecting specifc components. Guidelines are given for coordinating combinations of line-side and load-side devices. Acceptance testing and maintenance guidelines are provided so that reliable operation can be verifed and maintained.

This recommended practice does not cover the selection and application of circuit breakers such as ground-fault circuit interrupters (GFCIs), marine circuit breakers, definite purpose circuit breakers, and supplementary circuit protectors. This recommended practice also does not discuss dc applications.