AMERICAN NATIONAL STANDARD PREFERRED RATINGS, RELATED REQUIREMENTS, AND APPLICATION RECOMMENDATIONS FOR LOW-VOLTAGE POWER CIRCUIT BREAKERS AND AC POWER CIRCUIT PROTECTORS.

This publication represents standard practice in the United States relating to low-voltage power circuit breakers and power circuit protectors. It specifically does not apply to molded-case circuit breakers. The rated short-circuit current of the devices covered in this standard is expressed in rms symmetrical current as compared to rms total current. The current revision includes the addition of overload switching requirements and endurance requirements for low-voltage ac power circuit breakers, and modifies Table 6 as to application of circuit breakers to motors. It also includes the preferred control voltages and their ranges for low-voltage power circuit breakers and ac power circuit protectors in Table 23. This publication now also covers standard preferred ratings and related requirements for low-voltage dc power circuit breakers, anode circuit breakers, integrally fused low-voltage ac power circuit breakers, and low-voltage ac power circuit protectors.