The scope of this standard includes the following enclosed low-voltage ac power circuit breakers: Stationary or drawout type of two-@ three-@ or four-pole construction with one or more rated maximum voltages of 635 V (600 V for units incorporating fuses)@ 508 V@ and 254 V for application on systems having nominal voltages of 600 V@ 480 V@ and 240 V Unfused or fused type Manually operated or power operated@ with or without electromechanical or electronic trip devices Fused drawouts consisting of current-limiting fuses in a drawout assembly intended to be connected in series with a low-voltage ac power circuit breaker to form a nonintegrally fused circuit breaker NOTE??In this standard@ the term circuit breaker shall mean enclosed low-voltage ac power circuit breaker@ either fused or unfused. The term unfused circuit breaker shall mean a circuit breaker without either integrally or nonintegrally mounted fuses@ and the term fused circuit breaker shall mean a circuit breaker incorporating currentlimiting fuses.1 This document applies to both integrally and nonintegrally fused circuit breakers. 1 Notes in text@ tables@ and figures of a standard are given for information only and do not contain requirements needed to implement this standard.