Full Description
Scope
The scope of this standard includes the following enclosed low-voltage ac power circuit breakers:a) 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 Vb) Unfused or fused typec) Manually operated or power operated, with or without electromechanical or electronic trip devicesd) 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 breakerNOTE--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.This document applies to both integrally and nonintegrally fused circuit breakers.Abstract
Revision Standard - Inactive - Superseded.The following enclosed low-voltage ac power circuit breakers are covered in this standard: a) stationary or draw-out type of two-, three-, or four-pole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; b) unfused or fused circuit breakers; c) manually or power operated; and d) with or without electromechanical or electronic trip devices. Service conditions, ratings, functional components, temperature limitations and classifications of insulating materials, insulation (dielectric) withstand voltage requirements,test procedures, and application are discussed in this standard.