1、C22.2 No. 248.12-11Low-voltage fuses Part 12: Class R fusesLegal Notice for StandardsCanadian Standards Association (CSA) standards are developed through a consensus standards development process approved by the Standards Council of Canada. This process brings together volunteers representing varied
2、 viewpoints and interests to achieve consensus and develop a standard. Although CSA administers the process and establishes rules to promote fairness in achieving consensus, it does not independently test, evaluate, or verify the content of standards.Disclaimer and exclusion of liabilityThis documen
3、t is provided without any representations, warranties, or conditions of any kind, express or implied, including, without limitation, implied warranties or conditions concerning this documents fitness for a particular purpose or use, its merchantability, or its non-infringement of any third partys in
4、tellectual property rights. CSA does not warrant the accuracy, completeness, or currency of any of the information published in this document. CSA makes no representations or warranties regarding this documents compliance with any applicable statute, rule, or regulation. IN NO EVENT SHALL CSA, ITS V
5、OLUNTEERS, MEMBERS, SUBSIDIARIES, OR AFFILIATED COMPANIES, OR THEIR EMPLOYEES, DIRECTORS, OR OFFICERS, BE LIABLE FOR ANY DIRECT, INDIRECT, OR INCIDENTAL DAMAGES, INJURY, LOSS, COSTS, OR EXPENSES, HOWSOEVER CAUSED, INCLUDING BUT NOT LIMITED TO SPECIAL OR CONSEQUENTIAL DAMAGES, LOST REVENUE, BUSINESS
6、INTERRUPTION, LOST OR DAMAGED DATA, OR ANY OTHER COMMERCIAL OR ECONOMIC LOSS, WHETHER BASED IN CONTRACT, TORT (INCLUDING NEGLIGENCE), OR ANY OTHER THEORY OF LIABILITY, ARISING OUT OF OR RESULTING FROM ACCESS TO OR POSSESSION OR USE OF THIS DOCUMENT, EVEN IF CSA HAS BEEN ADVISED OF THE POSSIBILITY OF
7、 SUCH DAMAGES, INJURY, LOSS, COSTS, OR EXPENSES.In publishing and making this document available, CSA is not undertaking to render professional or other services for or on behalf of any person or entity or to perform any duty owed by any person or entity to another person or entity. The information
8、in this document is directed to those who have the appropriate degree of experience to use and apply its contents, and CSA accepts no responsibility whatsoever arising in any way from any and all use of or reliance on the information contained in this document. CSA is a private not-for-profit compan
9、y that publishes voluntary standards and related documents. CSA has no power, nor does it undertake, to enforce compliance with the contents of the standards or other documents it publishes. Intellectual property rights and ownershipAs between CSA and the users of this document (whether it be in pri
10、nted or electronic form), CSA is the owner, or the authorized licensee, of all works contained herein that are protected by copyright, all trade-marks (except as otherwise noted to the contrary), and all inventions and trade secrets that may be contained in this document, whether or not such inventi
11、ons and trade secrets are protected by patents and applications for patents. Without limitation, the unauthorized use, modification, copying, or disclosure of this document may violate laws that protect CSAs and/or others intellectual property and may give rise to a right in CSA and/or others to see
12、k legal redress for such use, modification, copying, or disclosure. To the extent permitted by licence or by law, CSA reserves all intellectual property rights in this document.Patent rightsAttention is drawn to the possibility that some of the elements of this standard may be the subject of patent
13、rights. CSA shall not be held responsible for identifying any or all such patent rights. Users of this standard are expressly advised that determination of the validity of any such patent rights is entirely their own responsibility.Authorized use of this documentThis document is being provided by CS
14、A for informational and non-commercial use only. The user of this document is authorized to do only the following:If this document is in electronic form:.load this document onto a computer for the sole purpose of reviewing it;.search and browse this document; and.print this document if it is in PDF
15、format. Limited copies of this document in print or paper form may be distributed only to persons who are authorized by CSA to have such copies, and only if this Legal Notice appears on each such copy.In addition, users may not and may not permit others to.alter this document in any way or remove th
16、is Legal Notice from the attached standard;.sell this document without authorization from CSA; or.make an electronic copy of this document.If you do not agree with any of the terms and conditions contained in this Legal Notice, you may not load or use this document or make any copies of the contents
17、 hereof, and if you do make such copies, you are required to destroy them immediately. Use of this document constitutes your acceptance of the terms and conditions of this Legal Notice.CSA Standards Update ServiceC22.2 No. 248.12-11May 2011Title:Low-voltage fuses Par t 12: Class R fusesPagination:14
18、 pages, each dated May 2011To register for e-mail notification about any updates to this publicationgo to www.ShopCSA.caclick on E-mail Services under MY ACCOUNTclick on CSA Standards Update ServiceThe List ID that you will need to register for updates to this publication is 2421211.If you require a
19、ssistance, please e-mail techsupportcsa.ca or call 416-747-2233.Visit CSAs policy on privacy at www.csagroup.org/legal to find out how we protect your personal information.Blank pageAssociation of Standardization and CertificationNMX-J-009/248/12-ANCESecond EditionCanadian Standards AssociationCSA C
20、22.2 No. 248.12-11Third EditionUnderwriters Laboratories Inc.UL 248-12Third EditionLow-Voltage Fuses Part 12: Class R FusesMay 13, 2011ANSI/UL 248-12-2011Commitment for AmendmentsThis standard is issued jointly by the Association of Standardization and Certification (ANCE), theCanadian Standards Ass
21、ociation (CSA), and Underwriters Laboratories Inc. (UL). Comments orproposals for revisions on any part of the standard may be submitted to ANCE, CSA, or UL at anytime.Revisions to this standard will be made only after processing according to the standards developmentprocedures of ANCE, CSA, and UL.
22、 CSA and UL will issue revisions to this standard by means of anew edition or revised or additional pages bearing their date of issue. ANCE will incorporate the samerevisions into a new edition of the standard bearing the same date of issue as the CSA and UL pages.Copyright 2011Rights reserved in fa
23、vor of ANCE.ISBN 978-1-55491-638-2 2011 Canadian Standards AssociationAll rights reserved. No part of this publication may be reproduced in any form whatsoever without theprior permission of the publisher.CSA Standards are subject to periodic review, and suggestions for their improvement will be ref
24、erredto the appropriate committee. To submit a proposal for change to CSA Standards, please send thefollowing information to inquirescsa.ca and include Proposal for change in the subject line:Standard designation (number); relevant clause, table, and/or figure number; wording of the proposedchange;
25、and rationale for the change.To purchase CSA Standards and related publications, visit CSAs Online Store at www.ShopCSA.ca orcall toll-free 1-800-463-6727 or 416-747-4044.Copyright 2011 Underwriters Laboratories Inc.ULs Standards for Safety are copyrighted by UL. Neither a printed nor electronic cop
26、y of a Standardshould be altered in any way. All of ULs Standards and all copyrights, ownerships, and rights regardingthose Standards shall remain the sole and exclusive property of UL.This ANSI/UL Standard for Safety consists of the Third Edition including revisions through May 13,2011. The most re
27、cent designation of ANSI/UL 248-12 as an American National Standard (ANSI)occurred on May 13, 2011. ANSI approval for a standard does not include the Cover Page, TransmittalPages, Title Page (front and back), or the Preface.Comments or proposals for revisions on any part of the Standard may be submi
28、tted to UL at any time.Proposals should be submitted via a Proposal Request in ULs On-Line Collaborative StandardsDevelopment System (CSDS) at http:/.To purchase UL Standards, visit Comm 2000 at http:/m- call toll-free 1-888-853-3503.CONTENTSPreface .41 General 61.1 Scope .64 Classification .65 Char
29、acteristics 65.2 Voltage rating 65.3 Current rating 65.5 Interrupting rating .75.6 Peak let-through current and clearing I2t characteristics .77 Construction 87.1 Dimensions 88 Tests .128.2 Verification of temperature rise and current-carrying capacity .128.3 Verification of overload operation 138.4
30、 Verification of operation at rated voltage .138.5 Verification of peak let-through current and clearing I2t characteristics .14MAY 13, 2011 NMX-J-009/248/12-ANCE CSA C22.2 NO. 248.12-11 UL 248-12 3PrefaceThis is the harmonized ANCE, CSA, and UL standard for Low-Voltage Fuses Part 12: Class R Fuses.
31、It is the second edition of NMX-J-009/248/12-ANCE, the third edition of CSA C22.2 No. 248.12-11, andthe third edition of UL 248-11. This edition of NMX-J-009-248/12-ANCE cancels the previous editionpublished in 2000. This edition of CSA C22.2 No. 248.12-11 supersedes the previous edition published i
32、n2000.This harmonized standard was prepared by the Association of Standardization and Certification (ANCE),the Canadian Standards Association (CSA), and Underwriters Laboratories Inc., (UL).This Standard is considered suitable for use for conformity assessment within the stated scope of theStandard.
33、The present Mexican Standard was developed by the CT 32 from the Comite de Normalizacion de laAsociacion de Normalizacion y Certificacion, A.C., CONANCE, with the collaboration of the fusemanufacturers and users.This standard was reviewed by the CSA Subcommittee on Fuses and Fuseholders, under the j
34、urisdictionof the CSA Technical Committee on Industrial Products and the CSA Strategic Steering Committee onRequirements for Electrical Safety, and has been formally approved by the CSA Technical Committee.This standard has been approved by the American National Standards Institute (ANSI) as an Amer
35、icanNational Standard.A UL standard is current only if it incorporates the most recently adopted revisions, all of which areitemized on the transmittal notice that accompanies the latest set of revised requirements.Where reference is made to a specific number of samples to be tested, the specified n
36、umber is to beconsidered a minimum quantity.Note: Although the intended primary application of this standard is stated in its scope, it is important to note thatit remains the responsibility of the users of the standard to judge its suitability for their particular purpose.Level of HarmonizationThis
37、 standard is published as an identical standard for ANCE, CSA, and UL. An identical standard is astandard that is exactly the same in technical content except for national differences resulting fromconflicts in codes and governmental regulations. Presentation is word for word except for editorialcha
38、nges.InterpretationsThe interpretation by the standards development organization of an identical or equivalent standard isbased on the literal text to determine compliance with the standard in accordance with the proceduralrules of the standards development organization. If more than one interpretat
39、ion of the literal text has beenidentified, a revision is to be proposed as soon as possible to each of the standards developmentorganizations to more accurately reflect the intent.MAY 13, 2011NMX-J-009/248/12-ANCE CSA C22.2 NO. 248.12-11 UL 248-124ANCE Effective DateThe effective date for ANCE will
40、 be announced through the Diario Oficial de la Federacin (OfficialGazette) and is indicated on the cover page.CSA Effective DateThe effective date for CSA International will be announced through CSA Informs or a CSA certificationnotice.UL Effective DateAs of May 13, 2011 all products Listed or Recog
41、nized by UL must comply with the requirements in thisstandard.A UL effective date is one established by Underwriters Laboratories Inc. and is not part of the ANSIapproved standard.MAY 13, 2011 NMX-J-009/248/12-ANCE CSA C22.2 NO. 248.12-11 UL 248-12 5Low-Voltage Fuses Part 12: Class R fuses1 GeneralN
42、OTE This Part is intended to be read together with the Standard for Low-Voltage Fuses Part 1: General Requirements,hereafter referred to as Part 1. The numbering of the Clauses in this Part corresponds to like numbered Clauses in Part1. The requirements of Part 1 apply unless modified by this Part.
43、For Clauses not shown below, refer to the Standard forLow-Voltage Fuses Part 1: General Requirements, NMX-J-009/248/1-ANCE CAN/CSA C22.2 No. 248.1-11 UL248-1.1.1 ScopeThis Part applies to Class R fuses rated 600 A or less and either 250 or 600 V ac. DC ratings are optional.4 ClassificationClass R fu
44、ses are non-renewable and current-limiting, with an interrupting rating of 200,000 A. Class Rfuses are divided into sub-classes RK1 and RK5 and are physically interchangeable for the same currentand voltage ratings. Class RK1 fuses have lower specified maximum peak let-through current and clearingI2
45、t characteristics. Each of the voltage ratings, 250 and 600 V ac, is divided into six body sizes. Themaximum current rating, In, for each size is specified in this Standard. Time-delay ratings are optional.5 Characteristics5.2 Voltage ratingFor AC, the rating shall be 250 or 600 V ac in accordance w
46、ith dimensions shown in Figures A and B.The DC voltage rating may be different from the AC rating.5.3 Current ratingRefer to Figure A for range of current ratings in each body size for each voltage rating.MAY 13, 2011NMX-J-009/248/12-ANCE CSA C22.2 NO. 248.12-11 UL 248-1265.5 Interrupting ratingFor
47、AC, 200,000 A, or 300,000 A at the manufacturers option (300,000 not applicable in Mexico).For DC, the preferred ratings are 10,000, 20,000, 50,000, 100,000, 150,000, 200,000, or 300,000A.5.6 Peak let-through current and clearing I2t characteristicsMaximum values of peak let-through current and clea
48、ring I2t Class RK1 and Class RK5 fuses are givenin Table A (see 8.5.3). Peak let-through currents shall not exceed the levels defined by the appropriateLet Through Function specified in Table A, as verified through measurement of peak let-through currentsat 25, 50, 100, 200, and, if applicable, 300
49、kA.Clearing I2t values recorded shall not exceed the limits specified in Table A as verified throughmeasurement of clearing I2t values at 25, 50, 100, 200, and, if applicable, 300 kA.Table A Maximum peak let-through current and clearing I2t for Class R fusesCurrentratingIn,ABetweenthreshold and 25kAAt 50 kA At 100 kA At 200 kA At 300 kA, ifapplicablePeakLet-throughFunctionaPeaklet-throughcurrent,kAI2t,ampere-squaredseconds3103Peaklet-throughcurrent,kAI2t,ampere-squaredseconds3103P
