1、UL 474ISBN 1-55989-415-6DehumidifiersUnderwriters Laboratories Inc. (UL)333 Pfingsten RoadNorthbrook, IL 60062-2096UL Standard for Safety for Dehumidifiers, UL 474Seventh Edition, Dated June 3, 1993Revisions: This Standard contains revisions through and including March 18, 2002.UL Standards for Safe
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5、onding item.Future Effective Date ReferencesMarch 18, 2004 Paragraph 8.9 and Section 40AThe new and revised requirements are substantially in accordance with ULs Bulletin(s) on this subjectdated July 13, 2001. The bulletin(s) is now obsolete and may be discarded.The revisions dated March 18, 2002 in
6、clude a reprinted title page (page1) for this Standard.As indicated on the title page (page 1), this UL Standard for Safety is an American National Standard.Attention is directed to the note on the title page of this Standard outlining the procedures to be followedto retain the approved text of this
7、 ANSI/UL Standard.As indicated on the title page (page1), this UL Standard for Safety 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 r
8、equirements for that product and service,or if there are questions regarding the accuracy of this Standard.ULs Standards for Safety are copyrighted by UL. Neither a printed copy of a Standard, nor the distributiondiskette for a Standard-on-Diskette and the file for the Standard on the distribution d
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10、 by any means, electronic, mechanical photocopying, recording, or otherwisewithout prior permission of UL.MARCH 18, 2002 UL 474 tr1Revisions 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 prov
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21、ages beingviewed for their own fair and/or practical internal use.The requirements 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 p
22、rior text for requirements that have been revised and that have a future effective dateare located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice.New product submittals made prior to a specified future effective date will be judged under all of therequirements in this Stand
23、ard including those requirements with a specified future effective date, unlessthe applicant specifically requests that the product be judged under the current requirements. However, ifMARCH 18, 2002 UL 474tr2the applicant elects this option, it should be noted that compliance with all the requireme
24、nts in thisStandard will be required as a condition of continued Listing and Follow-Up Services after the effectivedate, and understanding of this should be signified in writing.Copyright 2002 Underwriters Laboratories Inc.This Standard consists of pages dated as shown in the following checklist:Pag
25、e Date1-8.March 18, 20029.June 3, 199310.March 31, 199811-16B .March 18, 200217.June 3, 199318-20B .March 18, 200221.April 23, 199622.March 31, 199823-26.March 18, 200226A.November 5, 199726B .March 18, 200226C-26D .April 23, 199627-28 .June 3, 199329-30B .March 18, 200231-33 .June 3, 199334-34B .Ap
26、ril 23, 199635.June 3, 199336-38.March 18, 200238A-38B .March 31, 199839.June 3, 199340.April 23, 199641-42B .March 18, 200243.March 31, 199844.June 3, 199345-46A .March 18, 200246B .March 31, 199847.June 3, 199348.March 31, 199849-50.March 18, 200251-52 .April 23, 199653-54 .June 3, 1993A1 .March 3
27、1, 1998A2.June 3, 1993MARCH 18, 2002 UL 474 tr3MARCH 18, 2002 UL 474tr4No Text on This PageJUNE 3, 1993(Title Page Reprinted: March 18, 2002)1UL 474Standard for DehumidifiersFirst Edition August, 1957Second Edition November, 1969Third Edition June, 1973Fourth Edition September, 1978Fifth Edition Jul
28、y, 1981Sixth Edition August, 1987Seventh EditionJune 3, 1993The most recent designation of ANSI/UL 474 as an American National Standard(ANSI) occurred on November 26, 2001.This ANSI/UL Standard for Safety, which consists of the seventh edition (withrevisions through March 18, 2002), is under continu
29、ous maintenance, wherebyeach revision is ANSI approved upon publication. Comments or proposals forrevisions on any part of the Standard may be submitted to UL at any time. Writtencomments are to be sent to the UL-Northbrook Standards Department, 333Pfingsten Road, Northbrook, IL 60062.An effective d
30、ate included as a note immediately following certain requirementsis one established by Underwriters Laboratories Inc. and is not part of the ANSIStandard.The Department of Defense (DoD) has adopted UL 474 on January 18, 1994.The publication of revised pages or a new edition of this Standard will not
31、invalidate the DoD adoption.Revisions of this Standard will be made by issuing revised or additional pagesbearing their date 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 s
32、et of revised requirements.ISBN 1-55989-415-6COPYRIGHT 1978, 2002 UNDERWRITERS LABORATORIES INC.ANSI/UL 474-2001MARCH 18, 2002DEHUMIDIFIERS - UL 4742No Text on This PageCONTENTSFOREWORD .4INTRODUCTION1 Scope .52 General .52.1 Components .52.2 Units of measurement .62.3 Undated references .63 Operati
33、ng Instructions .6CONSTRUCTION4 General .65 Assembly .66 Enclosures .97 Polymeric Materials Application .97.1 General .97.2 Material classification .107.3 Ignition sources .107.4 Enclosures .107.5 Functional and structural parts .107.6 Nonfunctional parts .138 Supply Connections .159 Internal Wiring
34、 .1610 Bonding for Grounding .17ELECTRICAL COMPONENTS11 Capacitors .1912 Current-Carrying Parts .1913 Electric Heaters .2013.1 Heater elements .2013.2 Heater over-temperature control .20A14 Insulating Material .2115 Motors and Motor Overload Protection .2116 Switches and Controllers .2417 Electrical Spacings .2417.1 High-voltage circuits .2417.2 Low-voltage circuits .26AREFRIGERATION SYSTEM18 Refrigerants .26A19 Refrigerant Tubing and Fittings .26A20 Ref
