1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 493 Thermoplastic-Insulated Underground Feeder and Branch-Circuit CablesUL 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 Thermoplastic-Insulated Underground Feeder and Branch-Circuit Cables, UL 493 Ninth Edition, Dated June 1, 2007 Summary of Topics This revision of ANSI/UL 493 contains the followi
3、ng changes in requirements: 1. Removal of Tin/Lead Alloy as a Conductor Coating 2. Clarication of Markings Following the Type-Letter Designation Text that has been changed in any manner or impacted by ULs electronic publishing system is marked with a vertical line in the margin. Changes in requireme
4、nts are marked with a vertical line in the margin and are followed by an effective date note indicating the date of publication or the date on which the changed requirement becomes effective. The new and/or revised requirements are substantially in accordance with Proposal(s) on this subject dated M
5、arch 30, 2012. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form by any means, electronic, mechanical photocopying, recording, or otherwise without prior permission of UL. UL provides this Standard as is without warranty of a
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7、ther damages arising out of the use of or the inability to use this Standard, even if UL or an authorized UL representative has been advised of the possibility of such damage. In no event shall ULs liability for any damage ever exceed the price paid for this Standard, regardless of the form of the c
8、laim. Users of the electronic versions of ULs Standards for Safety agree to defend, indemnify, and hold UL 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 stor
9、ing an electronic Standard on the purchasers computer system. The requirements in this Standard are now in effect, except for those paragraphs, sections, tables, gures, and/or other elements of the Standard having future effective dates as indicated in the note following the affected item. The prior
10、 text for requirements that have been revised and that have a future effective date are located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice. The following table lists the future effective dates with the corresponding reference. MAY 30, 2012 UL 493 tr1UL COPYRIGHTED MATER
11、IAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Future Effective Date Reference May 30, 2013 Paragraphs 9.1 and 24.26 MAY 30, 2012 UL 493 tr2UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL JUNE 1, 2007
12、(Title Page Reprinted: May 30, 2012) 1 UL 493 Standard for Thermoplastic-Insulated Underground Feeder and Branch- Circuit Cables First Edition February, 1957 Second Edition August, 1968 Third Edition July, 1970 Fourth Edition July, 1975 Fifth Edition March, 1979 Sixth Edition February, 1983 Seventh
13、Edition October, 1988 Eighth Edition December, 1995 Ninth Edition June 1, 2007 This ANSI/UL Standard for Safety consists of the Ninth Edition including revisions through May 30, 2012. The most recent designation of ANSI/UL 493 as an American National Standard (ANSI) occurred on May 30, 2012. ANSI ap
14、proval for a standard does not include the Cover Page, Transmittal Pages, Title Page, or effective date information. 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 S
15、tandards Development System (CSDS) at http:/. ULs Standards for Safety are copyrighted by UL. Neither a printed nor electronic copy of a Standard should be altered in any way. All of ULs Standards and all copyrights, ownerships, and rights regarding those Standards shall remain the sole and exclusiv
16、e property of UL. COPYRIGHT 2012 UNDERWRITERS LABORATORIES INC. ANSI/UL 493-2012UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL JUNE 1, 2007 UL 493 2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DIST
17、RIBUTION WITHOUT PERMISSION FROM UL CONTENTS INTRODUCTION 1 Scope .4 2 Units of Measurement .4 3 References .4 CONSTRUCTION 4 General 5 5 Conductors .5 6 Insulation 6 7 Assembly of Multiple-Conductor Cables 7 7.1 General .7 7.2 Circuit conductors 7 7.3 Grounding conductor 8 8 Outer Covering on Multi
18、ple-Conductor Cables 9 9 Assemblies That Include Single-Conductor Type UF Cables 14 10 Submersible Water-Pump Cable Constructions .14 PERFORMANCE 11 Separability 16 12 Continuity 16 13 Vertical Flame Test .17 14 Vertical-Tray Flame Test .17 15 Dielectric Voltage-Withstand Test .18 16 Tension and Elo
19、ngation Test .19 17 Unwinding Test at Low Temperature 21 17.1 General .21 17.2 Preparation of specimens .21 17.3 Test equipment 21 17.4 Conduct of the test .22 17.5 Results .23 18 Conductor Pullout Test 23 19 Stability of Conguration Test 23 20 Impact Test 26 21 Crushing Resistance Test 28 22 Flow T
20、est 29 23 Sunlight Resistance Test 30 MARKINGS 24 Details .30 JUNE 1, 2007 UL 493 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL INTRODUCTION 1 Scope 1.1 These requirements cover 14 4/0 AWG single-conductor PVC-insulated and -jacketed unde
21、rground feeder and branch-circuit cable and at multiple-conductor PVC-jacketed underground feeder and branch-circuit cables containing two or three 14 6 AWG PVC-insulated circuit conductors with or without a grounding conductor. These Type UF cables are intended for use in accordance with Article 34
22、0 and other applicable parts of the National Electrical Code, ANSI/NFPA-70 in wiring systems operating at a potential of 600 V or less. Submersible water-pump cables and multiple-conductor assemblies to which a type-letter designation is not assigned are also covered in these requirements. 1.2 Multi
23、ple-conductor cable that is marked UF-B has a 75C (167F) jacket and conductors with insulation of 90C (194F) dry and at least 60C (140F) wet locations. Multiple-conductor cable that is marked UF has a 60C (140F) jacket and conductors with insulation for 60C (140F) dry and wet locations. Single-condu
24、ctor cable is marked UF and has an integral insulation and jacket for 60C (140F) dry and wet locations. The ampacity of all cables covered in these requirements is that of 60C (140F) conductors. 1.3 These requirements do not cover insulation other than PVC, round cables containing two or more circui
25、t conductors, at cables containing more than three circuit conductors, or multiple-conductor cables containing circuit conductors larger than 6 AWG. 2 Units of Measurement 2.1 In addition to being stated in the inch/pound units that are customary in the USA, each of the requirements in this standard
26、 is also stated in units that make the requirement conveniently usable in countries employing the metric system (practical SI). Equivalent although not necessarily exactly identical results are to be expected from applying a requirement in USA or metric terms. Equipment calibrated in metric units is
27、 to be used when a requirement is applied in metric terms. 3 References 3.1 Any undated reference to a code or standard appearing in the requirements of this standard shall be interpreted as referring to the latest edition of that code or standard. JUNE 1, 2007 UL 493 4UL COPYRIGHTED MATERIAL NOT AU
28、THORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CONSTRUCTION 4 General 4.1 Underground feeder and branch-circuit cable shall be designated as Type UF and shall comply in all respects with the applicable requirements for construction details and test performance. 4.2 Each
29、 of the materials used for the insulation, spacers, llers, jacket, and other non-metallic parts of a cable shall be resistant to fungi, moisture, and corrosion. In addition, each of the materials used as insulation on the circuit conductors shall be acceptable for use in wet locations. 4.3 Polypropy
30、lene, PVC, and glass are known to be resistant to fungi and hence are acceptable in this respect without exposure tests. Tests to determine the degree of resistance to fungi are to be made as indicated in the American Society for Testing and Materials Standard Practice for Determining Resistance of
31、Synthetic Polymeric Materials to Fungi ASTM G 21-96(2002) on materials not known to have the requisite property. Cotton, paper, jute, hemp, and the like are not acceptable whether treated or not. 5 Conductors 5.1 Only soft-annealed copper, copper-clad aluminum, or an acceptable aluminum alloy shall
32、be used for the conductor or conductors in a cable. Soft-annealed copper shall comply with the Standard Specication for Soft or Annealed Copper Wire ASTM B 3-01. Solid aluminum conductors in size 12 8 AWG shall comply with the requirements for aluminum-wire stock (aluminum-alloy conductor material).
33、 All other aluminum conductors shall comply with the requirements for semi-annealed 8000 series aluminum conductors in Section 10 of UL 1581. Copper-clad aluminum conductors shall comply with the requirements in Section 11 of UL 1581. In a given cable, all conductors shall be of the same metal. 5.2
34、The conductor in single-conductor cable shall not be smaller than 14 AWG and shall not be larger than 4/0 AWG if of copper, and shall not be smaller than 12 AWG and shall not be larger than 4/0 AWG if of aluminum or copper-clad aluminum. A copper circuit conductor in a multiple-conductor cable shall
35、 not be smaller than 14 AWG and shall not be larger than 6 AWG. An aluminum or copper-clad aluminum circuit conductor in a multiple-conductor cable shall not be smaller than 12 AWG and shall not be larger than 6 AWG. 5.3 The conductors in the 14 2 AWG single-conductor cables that comprise the pump c
36、ables mentioned in 10.1 shall be solid or stranded. The conductors in other 6 4/0 AWG single-conductor cable shall be stranded. Each 8 and 6 AWG circuit conductor in a multiple-conductor cable shall be stranded. Conductors shall comply with the requirements in the Standard for Thermoplastic-Insulate
37、d Wires and Cables, UL 83, except as modied in this Section. 5.4 A joint in a solid conductor or in one of the individual wires of a stranded conductor shall be made in a workmanlike manner and shall not increase the diameter of the solid conductor, the individual wire strand, or the overall strande
38、d conductor. A joint shall not be made in a stranded conductor as a whole but shall be made by separately joining each individual wire. A joint shall be made only before coverings, if any, are applied to an insulated conductor. The insulation applied to such joints shall be equivalent to that remove
39、d and shall have insulation-resistance and dielectric withstand-voltage characteristics complying with the Standard for Thermoplastic-Insulated Wires and Cables, UL 83. JUNE 1, 2007 UL 493 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 6 I
40、nsulation 6.1 The circuit conductors in a nished multiple-conductor cable that is marked UF-B shall not have any surface marking of the ampacity or temperature rating and shall comply with one of the following: a) NYLON JACKET OVER INSULATION The insulation and the nylon jacket shall comply with the
41、 thickness and other applicable requirements for Types THWN-2, THWN, and THHN thermoplastic-insulated wires. The markings THWN-2 , THWN , THHN , THWN OR THHN , and -B shall not be used. b) NO NYLON JACKET The insulation shall comply with the thickness requirements for a Type TW thermoplastic-insulat
42、ed wire using a PVC that complies with the requirements for both Type TW and THHN insulation (tensile strength and elongation complying with Table 50.155 of UL 1581 and deformation test conducted at 121.0 1.0C or 249.8 1.8F with a decrease of not more than 50 percent in the thickness of the PVC insu
43、lation). The surface marking -B is optional on the insulation. 6.2 In all single- and multiple-conductor cables that are marked UF (without the suffix -B ), the insulation employed on the circuit conductor or conductors shall comply with the applicable requirements for Type TW thermoplastic-insulate
44、d wire (the surface marking TW is optional on the insulation). In any cable, a grounding conductor shall be bare or shall be fully insulated in compliance with 7.3.3 and with the thickness and other requirements stated in this Section for the circuit conductors. 6.3 The insulation and jacket on sing
45、le-conductor cable shall be integral with one another. The average and minimum-at-any-point thicknesses of the PVC determined on specimens of nished cable shall not be less than indicated in Table 6.1. The method of preparing specimens, taking the measurements, and determining compliance shall be as
46、 specied in the Standard for Thermoplastic Insulated Wires and Cables, UL 83. 6.4 An insulation or jacket that is of material generically different from PVC (new material), or that is of the PVC material specied in this Standard yet does not comply with the short-term tests for the PVC insulation in
47、 Specic Materials, Section 50 of UL 1581, or with the tests for the PVC jacket in Table 8.1 of this Standard, shall be of a material and in thicknesses and with the temperature rating required for the specic underground feeder and branch-circuit cable type. The material shall be evaluated for the re
48、quested temperature rating as described in Long-Term Aging, Section 481 of UL 1581. Investigation of the electrical, mechanical, and physical characteristics of the cable using the material shall show the material to be comparable in performance to the PVC insulation or jacket material specied in th
49、is Standard. The investigation shall include tests such as crushing, impact, abrasion, deformation, heat shock, insulation resistance, and dielectric voltage-withstand. JUNE 1, 2007 UL 493 6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Table 6.1 Minimum acceptable thicknesses of integral insulation and jacket on single-conductor cable AWG size of conductor Minimum avera