Full Description

Scope

This guide applies to unfused low-voltage ac power circuit breakers of the 635 V maximum voltage class with separately-mounted current-limiting fuses for use on ac circuits with available short-circuit currents of 200 000 A (rms symmetrical) or less. Low-voltage ac fused power circuit breakers and combinations of fuses and molded-case circuit breakers are not covered by this guide. In this guide, the term circuit breaker means unfused low-voltage ac power circuit breaker.

Purpose

This guide sets forth recommendations believed essential for the selection of current-limiting fuses (see NEMA FU-1 and UL 248-1) for use in combination with low-voltage ac power circuit breakers, rated in accordance with IEEE Std C37.13¿¿¿ and applied in metal-enclosed low-voltage power circuit breaker switchgear in accordance with IEEE Std C37.20.1. NOTE--The combination of a circuit breaker and separately mounted fuses is limited to 600 V based on fuse maximum voltage ratings.

Abstract

Revision Standard - Active.Application recommendations to assist in selection of separately mounted current-limiting fuses to be installed in series with low-voltage ac power circuit breakers are provided in this guide.

Product Details

Published: 03/17/2016 ISBN(s): 9781504420907, 9781504420914, 9781504420891, 9781504407854, 9781504407847 Number of Pages: 20 File Size: 1 file , 1.4 MB Redline File Size: 2 files , 2.6 MB Product Code(s): STD20853, STDRL20853, STDPD20853, STDPDRL20853, STDPL20853