1、C22.2 No. 66.2-06(reaffirmed 2011)Low Voltage Transformers Part 2: General Purpose TransformersUpdate No. 1C22.2 No. 66.2-06November 2012Note: For information about the Standards Update Service, go to shop.csa.ca or e-mail techsupportcsagroup.org.Title: Low Voltage Transformers Part 2: General Purpo
2、se Transformers originally published April 2006The following revisions have been formally approved and are marked by a vertical line in the margin on the attached replacement pages:Revised Title page, copyright page, Contents, Preface, Clauses 8.5.9, 14.3, 26.6, 29.1.3, 29.2.1, 32, and 37.1, and Tab
3、les 8 and 9New NoneDeleted None Update your copy by inserting these revised pages.Keep the pages you remove for reference.CSA GroupCSA C22.2 No. 66.2-06First EditionUnderwriters Laboratories Inc.UL 5085-2First EditionLow Voltage Transformers Part 2: General Purpose TransformersApril 17, 2006(Title P
4、age Reprinted: November 30, 2012)ANSI/UL 5085-2-2012Commitment for AmendmentsThis standard is issued jointly by the Canadian Standards Association (operating as “CSA Group”) andUnderwriters Laboratories Inc. (UL). Comments or proposals for revisions on any part of the standardmay be submitted to CSA
5、 Group or UL at any time. Revisions to this standard will be made only afterprocessing according to the standards development procedures of CSA Group and UL. CSA Group andUL will issue revisions to this standard by means of a new edition or revised or additional pages bearingtheir date of issue.ISBN
6、 1-55436-210-5 2006 CSA GroupAll rights reserved. No part of this publication may be reproduced in any form whatsoever without theprior permission of the publisher.This Standard is subject to periodic review, and suggestions for its improvement will be referred to theappropriate committee. To submit
7、 a proposal for change, please send the following information toinquirescsagroup.org and include “Proposal for change” in the subject line: Standard designation(number); relevant clause, table, and/or figure number; wording of the proposed change; and rationalefor the change.To purchase CSA Group St
8、andards and related publications, visit CSA Groups Online Store atshopcsa.ca or call toll-free 1-800-463-6727 or 416-747-4044.Copyright 2012 Underwriters Laboratories Inc.ULs Standards for Safety are copyrighted by UL. Neither a printed nor electronic copy of a Standardshould be altered in any way.
9、All of ULs Standards and all copyrights, ownerships, and rights regardingthose Standards shall remain the sole and exclusive property of UL.The most recent designation of ANSI/UL 50852 as an American National Standard (ANSI) occurredon November 30, 2012. ANSI approval for a standard does not include
10、 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 submitted to UL at any time.Proposals should be submitted via a Proposal Request in ULs On-Line Collaborative StandardsDevelopment System (CSDS) at ht
11、tp:/.To purchase UL Standards, visit Comm 2000 at http:/m- call toll-free 1-888-853-3503.CONTENTSPreface .51 Scope .75 Mechanical Assembly .76 Enclosure 76.5 Openings 78 Connections 78.1 General .78.4 Pressure terminal connectors 88.5 Leads .88.6 Splice compartment .98.7 Wiring compartment 98.8 Wire
12、 bending space .98.9 Receptacles 1011 Spacings and Insulation .1011.4 Insulation used in lieu of spacings 1113 Current-Carrying Parts 1114 Cord-Connected Transformers .1115 Strain Relief 1217 Markings .1217.1 General .1217.3 Environmental condition enclosures 1317.4 Details 1317.5 Wiring .1418 Tests
13、 1521 Bonding Conductor Test .1626 Temperature (Heating) Test 1727 Voltage Measurement Test 1828 Impedance Test 1829 Dielectric Voltage-Withstand Test .1829.1 Applied potential .1829.2 Induced potential .1930 Overload Test 1931 Repeated Dielectric Voltage-Withstand Test 2032 Maximum Output Power and
14、 Short Circuit Tests for Line Cord-Connected Transformers 2033 Short Circuit Test on Transformers with Output Receptacles .2034 Maximum Output Power Test on Transformers with Output Receptacles 2135 Leakage Current Test .2136 Power Input Test .2337 Lifting or Mounting Means Test .2338 Strain Relief
15、Test .23Annex A (Informative)A1 Dielectric Voltage-Withstand Test .34NOVEMBER 30, 2012 CSA C22.2 NO. 66.2-06 UL 5085-2 3Annex C (Informative)C1 French Translations of Markings .35APRIL 17, 2006CSA C22.2 NO. 66.2-06 UL 5085-24PrefaceThis is the harmonized CSA Group and UL standard for low voltage tra
16、nsformers. It is the first edition ofCSA C22.2 No. 66.2 and the first edition of UL 5085-2. This harmonized standard has been jointly revisedon November 30, 2012. For this purpose, CSA Group and UL are issuing revision pages dated November30, 2012.This harmonized standard was prepared by a Technical
17、 Harmonization Committee comprised of membersfrom CSA Group, Underwriters Laboratories Inc. (UL), and representatives of the low voltage transformermanufacturing industry. The efforts and support of members of the Technical Harmonization Committeeare gratefully acknowledged.This Standard is consider
18、ed suitable for use for conformity assessment within the stated scope of theStandard.This standard was reviewed by the CSA Subcommittee on C22.2 No. 66, under the jurisdiction of the CSATechnical Committee on Industrial Products and the CSA Strategic Steering Committee on Requirementsfor Electrical
19、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 AmericanNational Standard.Where reference is made to a specific number of samples to be tested, the specified number is to beconsidered a mi
20、nimum quantity.Note: Although the intended primary application of this standard is stated in its scope, it is important to note that it remainsthe responsibility of the users of the standard to judge its suitability for their particular purpose.Level of harmonizationThis standard uses the IEC format
21、 but is not based on, nor is it to be considered equivalent to, an IECstandard. 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 all
22、owed for codes and governmental regulations as well as thoserecognized as being in accordance with NAFTA Article 905, for example, because of fundamental climatic,geographical, technological, or infrastructural factors, scientific justification, or the level of protection thatthe country considers a
23、ppropriate. Presentation is word for word except for editorial changes.Reasons for Differences from IECThe Technical Harmonization Committee identified the following IEC Standard within the scope of thisstandard: IEC 61558-1 (1998-07), Safety of power transformers, power supply units, and similar -
24、Part 1:General requirements.The THC determined that the safe use of transformers and reactors is critically dependent on the electricalsystem in which they are intended to be installed. Significant investigation is required to assess safety andsystem compatibility issues that may lead to harmonizati
25、on of traditional North American transformers andreactors with those presently addressed in the known IEC standards. The THC agreed such futureinvestigation might be facilitated by completion of harmonization of North American standards fortransformers and reactors.NOVEMBER 30, 2012 CSA C22.2 NO. 66
26、.2-06 UL 5085-2 5InterpretationsThe 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
27、 literal interpretation has been identified,a revision is to be proposed as soon as possible to each of the standards development organizations tomore accurately reflect the intent.CSA Group Effective DateThe effective date for CSA Group will be announced through CSA Informs or a CSA Group certifica
28、tionnotice.UL Effective DateThis Standard is now in effect.PartsThe Standard for Low Voltage Transformers is divided into the following parts:Part Number Standard Title Standard Number1 General Requirements CSA C22.2 No. 66.1/UL 5085-12 General Purpose Transformers CSA C22.2 No. 66.2/UL 5085-23 Clas
29、s 2 and Class 3 Transformers CSA C22.2 No. 66.3/UL 5085-3NOTES 1. Part 1 covers the general requirements for transformer characteristics, marking, construction, and tests. Additional specificrequirements are provided in the subsequent parts.2. Part 2 and Part 3 supplement requirements and/or modify
30、the corresponding clauses in Part 1 and should be appliedtogether with Part 1. The numbered clauses in Part 2 and Part 3 correspond to the numbered clauses in Part 1.NOVEMBER 30, 2012CSA C22.2 NO. 66.2-06 UL 5085-26PART 2: GENERAL PURPOSE TRANSFORMERS1 Scope1.1 As noted in Low Voltage Transformers P
31、art 1: General Requirements, UL 5085-1, or CSA C22.2No. 66.1, Low Voltage Transformers Part 1: General Requirements, the requirements of Part 2 cover:a) Air-cooled transformers and reactors for general use;b) Autotransformers;c) Ferroresonant transformers;d) Cord-connected transformers; ande) Transf
32、ormers incorporating overcurrent or over-temperature protective devices, transientvoltage surge protectors, or capacitors.1.7 These requirements do not cover Class 2 and Class 3 transformers (which are evaluated in Part 3).1.8 Part 2 is intended to be used in conjunction with Part 1. The numbering o
33、f the clauses in Part 2corresponds to the numbered clauses in Part 1. The requirements in Part 1 apply unless modified by Part2.5 Mechanical Assembly5.4 A transformer weighing more than 45 kg (100 lbs) shall be provided with a means for lifting by a forklift, cable, sling, or similar method. The lif
34、ting means may be provided on the transformer core or frame ifthe transformer has a removable top cover. The lifting means shall be subjected to the Lifting or MountingMeans Test in Clause 37.Note: The lifting means test does not apply to a transformer that is intended to be lifted from underneath b
35、y a fork lift orother method.6 Enclosure6.5 Openings6.5.2 Openings shall prevent passage of a straight rod 12.7 mm (0.5 in) in diameter. When the distancebetween live parts and the enclosure and between the plane of the ventilation opening and live parts is102 mm (4 in) or more, openings shall be co
36、nstructed so that they will prevent passage of a rod 19 mm(0.75 in) in diameter. When the distance between the plane of the opening and uninsulated live parts isless than 102 mm, the rod shall have a cross-section of 13.4 mm (0.53 in).8 Connections8.1 General8.1.4 A transformer shall have provision
37、for the connection of supply and load conductors, either in theform of busbars, leads, pressure terminal connectors, or terminal pads for pressure terminal connectors.APRIL 17, 2006 CSA C22.2 NO. 66.2-06 UL 5085-2 7Note: Studs or wire binding screws may be used for field connections when the full lo
38、ad current of the terminal is 24 A orless and the transformer is marked in accordance with Clause 17.5.5. The studs or wire binding screws may be used forthe field connection of 10 AWG (5.3 mm2) or smaller conductors.8.4 Pressure terminal connectors8.4.5 More than one wire connector may be provided
39、for a single connection point to allow for connectionof the various size conductors which require accommodation. In such case, each connector shall bemarked in accordance with Clause 17.5.7.8.5 Leads8.5.9 A transformer lead shall:a) Be of stranded wire.b) Not be smaller than 14 AWG (2.1 mm2) copper
40、or 12 AWG (3.3 mm2) aluminum.c) Have a minimum length of 152 mm (6 in) available for connection.22 AWG ( 0.35 mm2) copper wire may be used as a lead for a transformer when the transformer isprovided with a wiring compartment or is intended for mounting on an outlet box.Leads on component type transf
41、ormers shall have an ampacity suitable for the transformer rating but shallnot be smaller than 18 AWG (0.82 mm2). A secondary lead of a transformer of the type described inClause 6.4.6 of Part 1 shall have a minimum length of 457 mm (18 in) available for connection.8.5.10 When a transformer is not i
42、ntended for outlet box mounting and is not provided with a terminal orwinding compartment, the leads shall enter the enclosure either through a nipple or other means for theattachment of rigid metal conduit. Alternatively, the leads shall enter through separate holes that providea spacing of not les
43、s than 6.4 mm (0.25 in) between the conductors and not less than 12.7 mm (0.5 in)between the conductors and the plane of the transformer support.8.5.11 Transformers, and their external leads, intended for installation in other enclosures (e.g., controlcircuit transformers housed with industrial cont
44、rol equipment) may have:a) Primary and secondary leads in the same opening, when they have insulation suitable forthe highest voltage involved and a temperature rating of at least 105C (221F) andb) Metal grommets or smooth, folded edges.8.5.12 One of the secondary terminals or leads of an autotransf
45、ormer intended for operation on a circuitof 150 V or less to ground shall be identified for the connection of a grounded circuit conductor. It shall bedirectly connected to a similarly identified primary terminal or lead. The identification shall be as specifiedin Clause 17.5.1.NOVEMBER 30, 2012CSA
46、C22.2 NO. 66.2-06 UL 5085-2811.4 Insulation used in lieu of spacings11.4.10 With regard to the requirement in Clause 11.4.1 of Part 1, insulation and spacings shall not bespecified between windings that are intended for interconnection (i.e., series/parallel connections). Thosewindings shall comply
47、with the marking specified in Clause 17.5.14 and shall also be subjected to thedielectric voltage test specified in Clause 29.1.1.13 Current-Carrying Parts13.11 With regard to the requirement in Clause 13.2 of Part 1:a) An aluminum current-carrying part is not required to be plated if one or more in
48、ternalconnections are welded and if any connections to the part that are not welded are assembledusing a corrosion inhibiting compound andb) Plating is not necessary when a bus bar is welded to an aluminum pad to which pressureterminal connectors are to be bolted if a corrosion-inhibiting compound i
49、s provided along withinstructions for its application as specified in Clause 17.5.10.14 Cord-Connected Transformers14.2 A flexible cord, when used for connection to the supply circuit, shall comply with Clauses 14.3 14.6and be provided with an attachment plug. The attachment plug shall be polarized or of the grounding-type.14.3 A supply cord shall be:a) Of a type that is intended for the usage;b) Intended for use at a voltage and ampacity not less than the rated voltage and ampacity ofthe transformer;
