1、UL 60950ISBN 0-7629-0470-4Safety of InformationTechnology EquipmentUnderwriters Laboratories Inc. (UL)333 Pfingsten RoadNorthbrook, IL 60062-2096UL Standard for Safety for Information Technology Equipment, UL 60950Third Edition, Dated December 1, 2000Announcement Bulletin(s): This Standard contains
2、the announcement bulletin(s) dated July 23, 1999. Theannouncement bulletin is located at the end of the 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 back side of the title page (page 2) of this
3、 Standard outlining theprocedures to be followed to retain the approved text of this ANSI/UL Standard.As indicated on the back side of the title page (page 2), this UL Standard for Safety has been adopted bythe Department of Defense.The master for this Standard at ULs Northbrook Office is the offici
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18、s 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that have been revised and that have a future effective dateare located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice.New product submittals
19、 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, unlessthe applicant specifically requests that the product be judged under the current requirements. However, ifthe appli
20、cant elects this option, it should be noted that compliance with all the requirements in thisStandard will be required as a condition of continued Listing, Recognition, and Follow-Up Services afterthe effective date, and understanding of this should be signified in writing.Copyright 2000 Underwriter
21、s Laboratories Inc.This Standard consists of pages dated as shown in the following checklist:Page Date1-430 .December 1, 2000DECEMBER 1, 2000 UL 60950tr2Safety of Information Technology EquipmentDecember 1, 2000This national standard is based on publication IEC 60950, Third Edition (1999).CSA Intern
22、ationalCAN/CSA-C22.2 No. 60950-00Third EditionUnderwriters Laboratories Inc.UL 60950Third EditionANSI/UL 60950-2000Commitment for AmendmentsThis Standard is issued jointly by CSA International and UnderwritersLaboratories Incorporated. Amendments to this Standard will be made only afterprocessing ac
23、cording to the Standards writing procedures by both CSAInternational and Underwriters Laboratories Incorporated.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 revisio
24、ns, all of which are itemized on the transmittal noticethat accompanies the latest set of revised requirements.Approval of UL 60950 as an AmericanNational Standard is maintained usingthe continuous maintenance process.Comments or proposals for revisionson any part of the Standard may besubmitted to
25、UL at any time. Writtencomments are to be sent to theUL-SC Standards Department, 1655Scott Blvd., Santa Clara, CA 95050.The most recent approval of UL60950 as an American NationalStandard (ANSI) occurred on October11, 2000 and covers the Third Edition.The U.S. Department of Defense(DoD) has adopted
26、UL 1950 onDecember 21, 1994. The publicationof revised pages or a new edition ofthis Standard will not invalidate theDoD adoption.ISBN 1-55324-222-XCopyright 2000CSA InternationalAll rights reserved. No part of thispublication may be reproduced in anyform whatsoever without the priorpermission of th
27、e publisher.ISBN 0-7629-0470-4Copyright 2000Underwriters Laboratories Inc.CONTENTSPREFACE .10FOREWORD (CSA) .13FOREWORD (UL) .14FOREWORD .15INTRODUCTION .170 Principles of safety .170.1 General principles of safety .170.2 Hazards .180.3 Materials and components .221 General .231.1 Scope .231.2 Defin
28、itions .251.3 General requirements .371.4 General conditions for tests .391.5 Components .441.6 Power interface .471.7 Markings and instructions .482 Protection from hazards .562.1 Protection from electric shock and energy hazards .562.2 SELV circuits .642.3 TNV circuits .672.4 Limited current circu
29、its .722.5 Limited power sources .742.6 Provisions for earthing and bonding .762.7 Overcurrent and earth fault protection in primary circuits .852.8 Safety interlocks .882.9 Electrical insulation .912.10 Clearances, creepage distances and distances through insulation .973 Wiring, connections and sup
30、ply .1183.1 General .1183.2 Connection to a.c. mains supplies .1223.3 Wiring terminals for connection of external conductors .1293.4 Disconnection from the a.c. mains supply .1333.5 Interconnection of equipment .1363.6 Special considerations for equipment connected to a centralized d.c. powersystem
31、DC mains voltages .1374 Physical requirements .1384.1 Stability .1384.2 Mechanical strength .1394.3 Design and construction .1444.4 Protection against hazardous moving parts .1504.5 Thermal requirements .1524.6 Openings in enclosures .1554.7 Resistance to fire .1645 Electrical requirements and simul
32、ated abnormal conditions .172DECEMBER 1, 2000 CAN/CSA-C22.2 NO. 60950-00 UL 60950 3DEDEDED2D25.1 Touch current and protective conductor current .1725.2 Electric strength .1825.3 Abnormal operating and fault conditions .1866 Connection to telecommunication networks .1916.1 Protection of telecommunica
33、tion network service personnel, and users of otherequipment connected to the network, from hazards in the equipment .1916.2 Protection of equipment users from overvoltages on telecommunicationnetworks .1946.3 Protection of the telecommunication wiring system from overheating .1986.4 Protection again
34、st overvoltage from power line crosses .1996.5 Acoustic tests .202Annex A (normative) Tests for resistance to heat and fireA.1 Flammability test for fire enclosures of movable equipment having a total massexceeding 18 kg, and of stationary equipment (see 4.7.3.2) .206A.1.1 Samples .206A.1.2 Conditio
35、ning of samples .206A.1.3 Mounting of samples .207A.1.4 Test flame .207A.1.5 Test procedure .207A.1.6 Compliance criteria .207A.2 Flammability test for fire enclosures of movable equipment having a total mass notexceeding 18 kg, and for material and components located inside fire enclosures (see4.7.
36、3.2 and 4.7.3.4) .207A.2.1 Samples .207A.2.2 Conditioning of samples .208A.2.3 Mounting of samples .208A.2.4 Test flame .208A.2.5 Test procedure .208A.2.6 Compliance criteria .209A.2.7 Alternative test .209A.3 High current arcing ignition test (see 4.7.3.2) .209A.3.1 Samples .209A.3.2 Test circuit .
37、209A.3.3 Test electrodes .210A.3.4 Test procedure .211A.3.5 Compliance criteria .211A.4 Hot wire ignition test (see 4.7.3.2) .211A.4.1 Samples .211A.4.2 Test circuit .211A.4.3 Mounting of samples .211A.4.4 Test procedure .212A.4.5 Compliance criterion .213A.5 Hot flaming oil test (see 4.6.2) .213A.5.1 Mounting of samples .
