UL 489 CRD-2018 UL Standard for Safety Molded-Case Circuit Breakers Molded-Case Switches and Circuit-Breaker Enclosures - Section Paragraph Reference 6 17 1 9 18 1 Subject Revisio.pdf

1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULUNDERWRITERS LABORATORIES INC. CERTIFICATION REQUIREMENT DECISIONThis Certification Requirement Decision is prepared by UL LLC. It is normative for the applicable ULProduct Certification Program(

2、s); however, it is currently not part of the UL Standard(s) referencedbelow.Product Category (CCN): DIMV, DIMV7, DIYA, DIYA7, DKPU2, DKPU8, DIVQ, DIVQ7,DKTY, DIRW, DIRW7, DIYV, DIYV7Standard Number: UL 489Standard Title: Standard for Molded-Case Circuit Breakers, Molded-Case Switches,and Circuit-Bre

3、aker EnclosuresEdition Date: October 24, 2016Edition Number: 13Section / Paragraph Reference: 6.17.1, 9.18.1Subject: Revision to Compliance criteria for Circuit breakers with a neutral pole.DECISION:6.17.1 4-pole constructions shall be permitted to be used for 3-phase circuits where a switched neutr

4、al isrequired. The fourth pole shall be provided with overcurrent protection of any value between 0 through 100percent of the other poles, inclusive either without overcurrent protection or with overcurrent protection of50 or 100 percent of the other poles. See 7.1.1.18, 7.17.1 - 7.17.3, and 9.18.1.

5、9.18.1 A 4-pole circuit breaker shall have the fourth (neutral) pole marked “Protection - _% In”. Thepercentage indicated shall be 0, 50 or 100 any value 0 through 100 inclusive, in increments of 10. LocationCategory B.RATIONALE FOR DECISION:This CRD expands the ability of circuit breakers to have n

6、eutral overcurrent protection at values other than0%, 50% and 100% of the other poles. Specific applications require neutral protections anywhere in therange of 0-100% of the other poles. Since the minimum and maximum of this range is already allowedand addressed by the standard, acceptance of inter

7、mediate values does not pose a technical concern.Copyright 2018 UL LLCUL LLC, in performing its functions in accordance with its objectives, does not guarantee or warrant thecorrectness of Certification Requirement Decisions it may issue or that they will be recognized or adoptedby anyone. Certifica

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10、t Decision is the current version and previously printed copies may be outdated.This document is published as a service to ULs certification customersUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULSTANDARD NUMBER: UL 489 -2-No Text on This Page