1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 5085-3 Low Voltage Transformers Part 3: Class 2 and Class 3 TransformersUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHT
2、ED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Low Voltage Transformers Part 3: Class 2 and Class 3 Transformers, UL 5085-3 First Edition, Dated April 17, 2006 Summary of Topics This revision to ANSI/UL 5085-3 is being issued
3、 to incorporate the following: Clarication of the Calibration Test of Overcurrent Protective Devices Clarication of Upper Rating Limit for Overcurrent Limiting Device in Class 2 Transformers Correction of Requirements for the Dielectric Voltage-Withstand After Overload Heating Test Reinstatement of
4、Requirements for the Separation of Circuits Correction of Maximum Temperature Rise for Class 120 (E) Insulation Systems Clarication of the Scope Regarding Cord-Connected Transformers Addition of Leakage Current Test for Cord-Connected Class 3 Transformers Text that has been changed in any manner or
5、impacted by ULs electronic publishing system is marked with a vertical line in the margin. The new and revised requirements are substantially in accordance with Proposal(s) on this subject dated June 29, 2012. All rights reserved. No part of this publication may be reproduced, stored in a retrieval
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7、lity or tness for any purpose. In no event will UL be liable for any special, incidental, consequential, indirect or similar damages, including loss of prots, lost savings, loss of data, or any other damages arising out of the use of or the inability to use this Standard, even if UL or an authorized
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9、L harmless from and against any loss, expense, liability, damage, claim, or judgment (including reasonable attorneys fees) resulting from any error or deviation introduced while purchaser is storing an electronic Standard on the purchasers computer system. The requirements in this Standard are now i
10、n effect, except for those paragraphs, sections, tables, gures, and/or other elements of the Standard having future effective dates as indicated in the preface. The prior text for requirements that have been revised and that have a future effective date are located after the Standard, and are preced
11、ed by a SUPERSEDED REQUIREMENTS notice. NOVEMBER 30, 2012 UL 5085-3 tr1UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL NOVEMBER 30, 2012 UL 5085-3 tr2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DIS
12、TRIBUTION WITHOUT PERMISSION FROM UL CSA Group CSA C22.2 No. 66.3-06 First Edition Underwriters Laboratories Inc. UL 5085-3 First Edition Low Voltage Transformers Part 3: Class 2 and Class 3 Transformers April 17, 2006 (Title Page Reprinted: November 30, 2012) ANSI/UL 5085-3-2012UL COPYRIGHTED MATER
13、IAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Commitment for Amendments This standard is issued jointly by the Canadian Standards Association (operating as “CSA Group”) and Underwriters Laboratories Inc. (UL). Comments or proposals for revisions on any part o
14、f the standard may be submitted to CSA Group or UL at any time. Revisions to this standard will be made only after processing according to the standards development procedures of CSA Group and UL. CSA Group and UL will issue revisions to this standard by means of a new edition or revised or addition
15、al pages bearing their date of issue. ISBN 1-55436-211-3 2006 CSA Group All rights reserved. No part of this publication may be reproduced in any form whatsoever without the prior permission of the publisher. This Standard is subject to periodic review, and suggestions for its improvement will be re
16、ferred to the appropriate committee. To submit a proposal for change, please send the following information to inquirescsagroup.org and include “Proposal for change” in the subject line: Standard designation (number); relevant clause, table, and/or gure number; wording of the proposed change; and ra
17、tionale for the change. To purchase CSA Group Standards and related publications, visit CSA Groups Online Store at shop.csa.ca or call toll-free 1-800-463-6727 or 416-747-4044. Copyright 2012 Underwriters Laboratories Inc. The most recent designation of ANSI/UL 5085-3 as a Reaffirmed American Nation
18、al Standard (ANS) occurred on November 30, 2012. ANSI approval for a standard does not include the Cover Page, Transmittal Pages, Title Page (front and back), or the Preface. Comments or proposals for revisions on any part of the Standard may be submitted to UL at any time. Proposals should be submi
19、tted via a Proposal Request in ULs On-Line Collaborative Standards Development System (CSDS) at http:/. To purchase UL Standards, visit Comm 2000 at http:/m- or call toll-free 1-888-853-3503.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CO
20、NTENTS Preface .5 1 Scope .7 4 Construction 7 6 Enclosure 8 6.1 General .8 8 Connections 9 8.2 Wiring terminals 9 8.5 Leads .9 11 Spacings and Insulation .10 11.2 Insulating material for mounting of low voltage live parts 10 11.3 Coil insulation 10 11.4 Insulation in lieu of spacings .10A 11.5 Spaci
21、ngs .10A 11.6 Separation of internal wiring circuits .10A 12 Switches, Protective Devices, and Wiring Devices .10B 12.3 Protective devices 10B 12.4 Separate current-limiting impedances .12 12.5 Overtemperature protective devices 12 17 Markings .12 17.1 General .12 17.3 Ratings .12 17.4 Details 13 18
22、 Tests 14 27 Open Circuit Secondary Voltage Test .15 28 Output Current and Power Test 16 28.1 Maximum current output of inherently limited transformers 16 28.2 Maximum current of non-inherently limited transformers .17 28.3 Maximum power of non-inherently limited transformers .17 29 Calibration Test
23、 of Overcurrent Protective Devices 19 30 Rated Secondary Current Test .19 31 Rated Output Heating Test .19 32 Dielectric Voltage-Withstand Test .21 32.1 General .21 32.2 Induced potential .22 33 Overload Heating Test 22 33.1 General .22 33.2 Procedure .23 34 Dielectric Voltage-Withstand After Overlo
24、ad Heating Test 24 35 Overload Test of Overcurrent or Overtemperature Protective Devices .24 36 Endurance Test of Automatically Reset Overtemperature Protective Devices .24 37 Strain Relief Test .25 Annex A (Informative) A1 Production Line Dielectric Voltage Withstand Test 31 NOVEMBER 30, 2012 CSA C
25、22.2 NO. 66.3-06 UL 5085-3 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Annex C (Informative) C1 French Translations of Markings .32 Annex D (Normative) D1 Class 3 Transformers .33 D1.1 General .33 D1.2 Marking .33 D1.3 Tests .34 D1.4 Le
26、akage current test .36 NOVEMBER 30, 2012 CSA C22.2 NO. 66.3-06 UL 5085-3 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Preface This is the harmonized CSA Group and UL standard for low voltage transformers. It is the rst edition of CSA C22
27、.2 No. 66.3 and the rst edition of UL 5085-3. This harmonized standard has been jointly revised on November 30, 2012. For this purpose, CSA Group and UL are issuing revision pages dated November 30, 2012. This harmonized standard was prepared by a Technical Harmonization Committee comprised of membe
28、rs from CSA Group, Underwriters Laboratories Inc. (UL), and representatives of the low voltage transformer manufacturing industry. The efforts and support of the members of the Technical Harmonization Committee are gratefully acknowledged. This Standard is considered suitable for use for conformity
29、assessment within the stated scope of the Standard. This standard was reviewed by the CSA Subcommittee on C22.2 No. 66, under the jurisdiction of the CSA Technical Committee on Industrial Products and the CSA Strategic Steering Committee on Requirements for Electrical Safety, and has been formally a
30、pproved by the CSA Technical Committee. This Standard has been approved by the American National Standards Institute (ANSI) as an American National Standard. Where reference is made to a specic number of samples to be tested, the specied number is to be considered a minimum quantity. Note: Although
31、the intended primary application of this standard is stated in its scope, it is important to note that it remains the responsibility of the users of the standard to judge its suitability for their particular purpose. Level of harmonization This standard uses the IEC format but is not based on, nor i
32、s it to be considered equivalent to, an IEC standard. This standard is published as an equivalent standard for CSA Group and UL. An equivalent standard is a standard that is substantially the same in technical content, except as follows: Technical national differences are allowed for codes and gover
33、nmental regulations as well as those recognized as being in accordance with NAFTA Article 905, for example, because of fundamental climatic, geographical, technological, or infrastructural factors, scientic justication, or the level of protection that the country considers appropriate. Presentation
34、is word for word except for editorial changes. Reasons for Differences from IEC The Technical Harmonization Committee identied the following IEC Standard within the scope of this standard: IEC 61558-1 (1998-07), Safety of power transformers, power supply units, and similar - Part 1: General requirem
35、ents. The THC determined that the safe use of transformers and reactors is critically dependent on the electrical system in which they are intended to be installed. Signicant investigation is required to assess safety and system compatibility issues that may lead to harmonization of traditional Nort
36、h American transformers and reactors with those presently addressed in the known IEC standards. The THC agreed such future investigation might be facilitated by completion of harmonization of North American standards for transformers and reactors. NOVEMBER 30, 2012 CSA C22.2 NO. 66.3-06 UL 5085-3 5U
37、L COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Interpretations The interpretation by the standards development organization of an identical or equivalent standard is based on the literal text to determine compliance with the standard in acco
38、rdance with the procedural rules of the standards development organization. If more than one literal interpretation has been identied, a revision is to be proposed as soon as possible to each of the standards development organizations to more accurately reect the intent. CSA Group Effective Date The
39、 effective date for CSA Group will be announced through CSA Informs or a CSA Group certication notice. UL Effective Date This Standard is now in effect. Parts The Standard for Low Voltage Transformers is divided into the following parts: Part Number Standard Title Standard Number 1 General Requireme
40、nts CSA C22.2 No. 66.1/UL 5085-1 2 General Purpose Transformers CSA C22.2 No. 66.2/UL 5085-2 3 Class 2 and Class 3 Transformers CSA C22.2 No. 66.3/UL 5085-3 NOTES 1. Part 1 covers the general requirements for transformer characteristics, marking, construction, and tests. Additional specic requiremen
41、ts are provided in the subsequent parts. 2. Part 2 and Part 3 supplement requirements and/or modify the corresponding clauses in Part 1 and should be applied together with Part 1. The numbered clauses in Part 2 and Part 3 correspond to the numbered clauses in Part 1. NOVEMBER 30, 2012 CSA C22.2 NO.
42、66.3-06 UL 5085-3 6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL PART 3: CLASS 2 AND CLASS 3 TRANSFORMERS 1 Scope 1.1 As noted in Low Voltage Transformers Part 1: General Requirements, UL 5085-1, or CSA C22.2 No. 66.1, Low Voltage Transfor
43、mers Part 1: General Requirements, the requirements in Part 3 cover Class 2 transformers for use with Class 2 circuits in accordance with the National Electrical Code, ANSI/NFPA 70, or the Canadian Electrical Code, Part I, CSA C22.1. They are intended for connection to essentially sinusoidal supply
44、sources. Advisory Note: For transformers intended for use in the United States, these requirements also cover Class 3 transformers for use with Class 3 circuits in accordance with the National Electrical Code, ANSI/NFPA 70, unless otherwise specied in this standard. See Annex D for Class 3 requireme
45、nts. 1.3 In addition to the items specied in Clause 1.3 of Part 1, the requirements of Part 3 do not cover: a) Power supplies (a transformer provided with a rectier is considered a power supply); b) Toy transformers; c) Cord and plug connected transformers other than Class 3; d) Direct plug-in trans
46、formers; e) Transformers intended for use in audio, radio, or television type appliances; or f) Other special types of transformers covered in requirements for other electrical devices or appliances. Advisory Note: The requirements of Part 3 do not cover transformers intended for use in the United S
47、tates having a nominal primary rating of more than 600 V and transformers having overvoltage taps rated over 660 V. 1.7 This part is intended to be used in conjunction with Part 1. The numbering of the clauses in Part 3 corresponds to the numbered clauses in Part 1. The requirements in Part 1 apply
48、unless modied by Part 3. 1.8 A Class 2 transformer that includes a separate current-limiting impedance such as a resistor or a positive temperature coefficient device (PTC) is covered by these requirements. 1.9 A Class 2 transformer that includes a resonance regulating circuit is covered by these re
49、quirements. 4 Construction 4.2 A Class 2 transformer shall have only one secondary winding, which shall be insulated from the primary winding. A winding having intermediate taps is considered a single winding. Note 1: Two or more secondary windings may be considered as a single winding and interposing insulation between the secondary windings is not required if the windings, when interconnected, are in compliance with the performance requirements for a singl