UL 20-2000 General Use Snap Switches.pdf

1、UL 200762905964General-Use Snap SwitchesUnderwriters Laboratories Inc. (UL)333 Pfingsten RoadNorthbrook, IL 60062-2096UL Standard for Safety for General-Use Snap Switches, UL 20Twelfth Edition, Dated September 22, 2000The new and/or revised requirements are substantially in accordance with ULs Bulle

2、tin(s) on this subjectdated May 16, 2000. The bulletin(s) is now obsolete and may be discarded.The following table lists the future effective dates with the corresponding item.Future Effective Dates ReferencesJune 1, 2005 Entire StandardAs indicated on the title page (page1), this UL Standard for Sa

3、fety has been adopted by the Departmentof Defense.The master for this Standard at ULs Northbrook Office is the official document insofar as it relates to aUL service and the compliance of a product with respect to the requirements for that product and service,or if there are questions regarding the

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6、t prior permission of UL.Revisions of UL Standards for Safety are issued from time to time. A UL Standard for Safety is currentonly if it incorporates the most recently adopted revisions.UL provides this Standard as is without warranty of any kind, either expressed or implied, including butnot limit

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8、se this Standard, even if UL or an authorized UL representative has been advised of thepossibility of such damage. In no event shall ULs liability for any damage ever exceed the price paid forthis Standard, regardless of the form of the claim.UL will attempt to answer support requests concerning ele

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10、intended. ULs support policies may change fromtime-to-time without notification.SEPTEMBER 22, 2000 UL 20 tr1UL reserves the right to change the format, presentation, file types and formats, delivery methods andformats, and the like of both its printed and electronic Standards without prior notice.Pu

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13、 a manner that this Standard may only be accessed by one userat a time and for which there is no possibility of multiple concurrent access.If a multiple-user version electronic Standard was purchased, one copy of the Standard may be stored ona single LAN file-server, or on the permanent storage devi

14、ce of a multiple-user computer, or on an Intranetserver. The number of concurrent users shall not exceed the number of users authorized.Electronic Standards are intended for on-line use, such as for viewing the requirements of a Standard,conducting a word search, and the like. Only one copy of the S

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16、andards purchasers, the printedcopy obtained by a purchaser may not look exactly like the on-line screen view or the printed Standard.An employee of an organization purchasing a UL Standard can make a copy of the page or pages beingviewed for their own fair and/or practical internal use.The requirem

17、ents in this Standard are now in effect, except for those paragraphs, sections, tables, figures,and/or other elements of the Standard having future effective dates as indicated in the note following theaffected item. The prior text for requirements that have been revised and that have a future effec

18、tive dateare located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice.New product submittals made prior to a specified future effective date will be judged under all of therequirements in this Standard including those requirements with a specified future effective date, unles

19、sthe applicant specifically requests that the product be judged under the current requirements. However, ifthe applicant elects this option, it should be noted that compliance with all the requirements in thisStandard will be required as a condition of continued Listed, Recognized, Classified, and F

20、ollow-UpServices after the effective date, and understanding of this should be signified in writing.Copyright 2000 Underwriters Laboratories Inc.This Standard consists of pages dated as shown in the following checklist:Page Date1-70.September 22, 2000A1-A2 .September 22, 2000B1-B6 .September 22, 200

21、0SEPTEMBER 22, 2000 UL 20tr2General-Use Snap SwitchesSeptember 22, 2000Canadian Standards AssociationCSA-C22.2 No. 111Third EditionUnderwriters Laboratories Inc.UL 20Twelfth EditionCommitment for AmendmentsThis Standard is issued jointly by Canadian Standards Association andUnderwriters Laboratories

22、 Incorporated. Amendments to this Standard will bemade only after processing according to the Standards writing procedures byboth Canadian Standards Association and Underwriters LaboratoriesIncorporated.Revisions of this Standard will be made by issuing revised or additional pagesbearing their date

23、of issue. A UL Standard is current only if it incorporates themost recently adopted revisions, all of which are itemized on the transmittal noticethat accompanies the latest set of revised requirements.The Department of Defense (DoD) has adopted UL 20 on December 4, 1981. Thepublication of revised p

24、ages or a new edition of this Standard will not invalidatethe DoD adoption.ISBN 1-55324-251-3Copyright 2000CSA InternationalAll rights reserved. No part of thispublication may be reproduced in anyform whatsoever without the priorpermission of the publisher.ISBN 0-7629-0596-4Copyright 2000Underwriter

25、s Laboratories Inc.CONTENTSPreface .5Foreword (CSA) .6Foreword (UL) .81 Scope .92 Definitions .103 General .113.1 New Product Evaluation .113.2 Components .113.3 Units of Measurement .123.4 Reference Publications .124 Construction .144.1 Enclosure .144.2 Lining .164.3 Bushings and Strain Relief .164

26、.4 Bases and Bodies .174.5 Current-Carrying Parts .184.6 Insulating Material .234.7 Actuating Members .244.8 Creepage Distances, Clearances, and Distances Through Sealing Compounds .244.9 Assembly .264.10 Provision for Grounding .275 Testing .295.1 General .295.2 Test Sequence .295.3 Tungsten-Filame

27、nt-Lamp Load Characteristics .355.4 Assembly Test .375.5 Test Conditions .385.6 Overload Test .385.7 Endurance Test .415.8 Temperature Test .425.9 Dielectric Voltage-Withstand Test .445.10 Security of Switch Leads Test .455.11 Push-In Terminal Tests .455.12 Effect of Heat on Actuating Members Test .

28、465.13 Switching Mechanism Test .465.14 Strain-Relief Test .485.15 Fault Current Test .485.16 Crushing Test .495.17 Resistance to Heat Test .496 Ratings .497 Markings .507.1 General .507.2 Supplementary Markings .527.3 Location .547.4 Tungsten .547.5 AC-Only Identification .557.6 Switch Termination

29、Restrictions .55SEPTEMBER 22, 2000 CSA-C22.2 NO. 111 UL 20 38 Self-Contained Switches for Use Without a Separate Outlet Box .578.1 General .578.2 Construction .578.3 Performance Testing .598.4 Markings and Instructions .66Figures .67Appendix AStandards for ComponentsA1 Component Standards .A1Appendi

30、x BCanadian Requirements for CO/ALR SwitchesB1 General .B1B2 Heat Cycling with Wire Disturbance .B3B3 Heat Cycling with Vibration .B4B4 Environmental .B5B5 Stripping Torque .B6SEPTEMBER 22, 2000CSA-C22.2 NO. 111 UL 204PrefaceThis is the common UL and CSA Standard for General-Use Snap Switches. It is

31、 the Third edition ofCSA-C22.2 No. 111 and the Twelfth edition of UL 20.This common Standard has been prepared by CSA International and Underwriters Laboratories Inc., andthe manufacturing industry. The efforts and support of NEMA (National Electrical ManufacturersAssociation) and EFC (Electro-Feder

32、ation of Canada) are gratefully acknowledged.This Standard was reviewed by the CSA Subcommittee on Standard C22.2 No. 111 and approved by theTechnical Committee on Wiring Products under the jurisdiction of the CSA Strategic Resource Group.This Standard will be submitted to the American National Stan

33、dards Institute (ANSI) for publication as asAmerican National Standard.Note: Although the intended primary application of this Standard is stated in its Scope, it is important tonote that it remains the responsibility of the users of the standard to judge its suitability for their particularpurpose.

34、UL Effective DateAs of June 1, 2005, all products Listed, Recognized, or Classified by UL must comply with therequirements in this Standard.Between September 22, 2000 and June 1, 2005, new product submittals to UL may be evaluated underall the requirements in this Standard or, if requested in writin

35、g evaluated under presently effectiverequirements only. The presently effective requirements are contained in the Eleventh edition of UL 20.CSA Effective DateThe effective date for CSA will be announced through CSA Informs or CSA Notification Notice.Level of HarmonizationThis standard is published a

36、s an equivalent standard. An equivalent standard is a standard that issubstantially the same in technical content, except as follows. Technical deviations are allowed for Codesand Governmental Regulations and those recognized as being in accordance with NAFTA Article 905, forexample because of funda

37、mental, climatic, geographical, technological, or infrastructural factors, scientificjustification or the level of protection that the country considers appropriate. Presentation is word for wordexcept for editorial changes.InterpretationsThe interpretation by the SDO of an equivalent or standard shall be based on the literal text to