1、NEMA Standards PublicationNational Electrical Manufacturers AssociationANSI/NEMA WC 70-2009Power Cables Rated 2000 Volts or Less for the Distribution of Electrical EnergyApproved as an American National Standard ANSI Approval Date: February 23, 2009 ANSI/NEMA WC 70-2009 ICEA S-95-658-2009 Power Cabl
2、es Rated 2000 Volts or Less for the Distribution of Electrical Energy Published by National Electrical Manufacturers Association 1300 North 17th Street, Suite 1752 Rosslyn, Virginia 22209 www.nema.org Copyright 2009 by the National Electrical Manufacturers Association and the Insulated Cable Enginee
3、rs Association, Incorporated. All rights, including translation into other languages, reserved under the Universal Copyright Convention, the Berne Convention for the Protection of Literary and Artistic Works, and the International and Pan American Copyright Conventions. NOTICE AND DISCLAIMER The inf
4、ormation in this publication was considered technically sound by the consensus of persons engaged in the development and approval of the document at the time it was developed. Consensus does not necessarily mean that there is unanimous agreement among every person participating in the development of
5、 this document. The National Electrical Manufacturers Association (NEMA) and the Insulated Cable Engineers Association Inc. (ICEA) standards and guideline publications, of which the document contained herein is one, are developed through a voluntary consensus standards development process. This proc
6、ess brings together persons who have an interest in the topic covered by this publication. While NEMA and ICEA administers the process and establishes rules to promote fairness in the development of consensus, they do not independently test, evaluate, or verify the accuracy or completeness of any in
7、formation or the soundness of any judgments contained in its standards and guideline publications. NEMA and ICEA disclaims liability for personal injury, property, or other damages of any nature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting f
8、rom the publication, use of, application, or reliance on this document. NEMA and ICEA disclaims and makes no guaranty or warranty, expressed or implied, as to the accuracy or completeness of any information published herein, and disclaims and makes no warranty that the information in this document w
9、ill fulfill any of your particular purposes or needs. NEMA and ICEA do not undertake to guarantee the performance of any individual manufacturers or sellers products or services by virtue of this standard or guide. In publishing and making this document available, NEMA and ICEA are not undertaking t
10、o render professional or other services for or on behalf of any person or entity, nor is NEMA and ICEA undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a
11、competent professional in determining the exercise of reasonable care in any given circumstances. Information and other standards on the topic covered by this publication may be available from other sources, which the user may wish to consult for additional views or information not covered by this p
12、ublication. NEMA and ICEA have no power, nor do they undertake to police or enforce compliance with the contents of this document. NEMA and ICEA do not certify, test, or inspect products, designs, or installations for safety or health purposes. Any certification or other statement of compliance with
13、 any health or safety-related information in this document shall not be attributable to NEMA and ICEA and is solely the responsibility of the certifier or maker of the statement. ANSI/NEMA WC 70-2009/ICEA S-95-658-2009 Page i 2009 By the National Electrical Manufacturers Association And the Insulate
14、d Cable Engineers Association. CONTENTS Page FOREWORD . iv Section 1 GENERAL . 1 1.1 SCOPE . 1 1.2 GENERAL INFORMATION 1 1.3 INFORMATION TO BE SUPPLIED BY PURCHASER 1 1.3.1 Characteristics of System on Which Cable is to be Used . 1 1.3.2 Quantities and Description of Cable 2 Section 2 CONDUCTOR . 3
15、2.0 GENERAL 3 2.1 PHYSICAL AND ELECTRICAL PROPERTIES . 3 2.1.1 Copper Conductors . 3 2.1.2 Aluminum Conductors . 3 2.1.3 Flexible Conductors . 4 2.2 CONDUCTOR SIZE UNITS . 4 2.3 CONDUCTOR DC RESISTANCE PER UNIT LENGTH 4 2.3.1 Direct Measurement of dc Resistance 4 2.3.2 Calculation of dc Resistance p
16、er Unit Length . 4 2.4 CONDUCTOR DIAMETER 5 Section 3 INSULATION . 17 3.1 MATERIAL . 17 3.2 INSULATION LEVELS . 17 3.3 INSULATION THICKNESSES . 17 3.3.1 The Thickness Of Insulation For Various Systems Shall Be Determined As Follows: 18 3.4 ADDITIONAL INSULATION THICKNESS FOR NON-SHEATHED SUBMARINE C
17、ABLES . 18 3.5 REPAIRS . 18 3.6 INSULATION GRADES AND REQUIREMENTS 18 3.6.1 The Classes Of Insulation And Their General Characteristics Are Given In Table 3-1. . 18 3.6.2 Voltage Tests . 18 3.6.3 Insulation Resistance 18 Section 4 COVERINGS . 28 4.1 JACKETS . 28 4.1.1 Cross-linked and Thermoplastic
18、Jackets - General . 28 4.1.2 Neoprene, Heavy-duty Black (CR-HD) . 28 4.1.3 Neoprene, General Purpose (CR-GP) . 28 4.1.4 Polyvinyl Chloride (PVC) 28 4.1.5 Low and Linear Low Density Polyethylene (LDPE & LLDPE) 28 4.1.6 Medium Density Polyethylene (MDPE) 28 4.1.7 High Density Polyethylene (HDPE) 28 4.
19、1.8 Nitrile-Butadiene/Polyvinyl-Chloride, Heavy Duty (NBR/PVC-HD) 28 4.1.9 Nitrile-butadiene/Polyvinyl-chloride, General-purpose Duty (NBR/PVC-GP) . 29 4.1.10 Chlorosulfonated Polyethylene, Heavy Duty (CSPE-HD) 29 4.1.11 Chlorinated Polyethylene, Thermoplastic (CPE-TP) 29 4.1.12 Chlorinated Polyethy
20、lene, Cross-Linked, Heavy Duty (CPE-XL-HD) . 29 4.1.13 Low Smoke Halogen Free Jackets 29 4.1.14 Thermoplastic Elastomer (TPE) 29 4.1.15 Optional Requirements 29 4.1.16 Separator Under Jacket . 29 4.1.17 Repairs 29 4.1.18 Jacket Thickness . 32 4.1.19 Irregularity Inspection of Jackets Over Cable 33 4
21、.2 METALLIC AND ASSOCIATED COVERINGS 34 ANSI/NEMA WC 70-2009/ICEA S-95-658-2009 Page ii 2009 By the National Electrical Manufacturers Association And the Insulated Cable Engineers Association. 4.2.1 General 34 4.3 DIVISION I . 35 4.3.1 Smooth Metallic Sheaths . 35 4.3.2 Flat Steel Tape Armor . 37 4.
22、3.3 Interlocked Metal Tape Armor . 39 4.3.4 Continuously Corrugated Metal Armor 40 4.3.5 Galvanized Steel Wire Armor 41 4.3.6 Bedding Over Cable Cores To Be Metallic Armored . 44 4.3.7 Outer Servings . 45 4.3.8 Cross-linked Jackets Over Metallic Coverings (Sheaths and Armors) 45 4.3.8.1 Material 45
23、4.3.9 Thermoplastic Jackets Over Metallic Coverings (Sheaths or Armors) 46 4.4 DIVISION II 47 4.4.1 Borehole Cable (Suspended at One End Only) 47 4.4.2 Dredge Cable 48 4.4.3 Shaft Cable 49 4.4.4 Vertical Riser Cable . 49 4.5 DIVISION III . 50 4.5.1 Buried Land Cables . 50 Section 5 ASSEMBLY, FILLERS
24、, CONDUCTOR IDENTIFICATION, GROUNDING CONDUCTORS AND SHIELDING. 51 5.1 ASSEMBLY OF MULTIPLE-CONDUCTOR CABLES . 51 5.1.1 Multiple-Conductor Round Cables With An Overall Covering . 51 5.1.2 Multiple-Conductor Assemblies Without Overall Covering 51 5.1.3 Flat Twin Cables 52 5.2 FILLERS . 52 5.3 CONDUCT
25、OR IDENTIFICATION 52 5.4 GROUNDING CONDUCTORS 52 5.5 SHIELDING 52 5.5.1 General 52 5.5.2 Metal Tapes . 53 Section 6 PRODUCTION TESTS AND TEST METHODS . 54 6.1 GENERAL 54 6.1.1 Testing and Test Frequency 54 6.1.2 Test Methods . 54 6.1.3 Number of Test Specimens from Samples 56 6.2 THICKNESS MEASUREME
26、NTS . 56 6.2.1 Beddings and Servings 56 6.2.2 Other Components 56 6.3 SAMPLES AND SPECIMENS FOR PHYSICAL AND AGING TESTS 56 6.3.1 General 56 6.3.2 Sampling 56 6.3.3 Size of Test Specimens . 56 6.3.4 Specimens with Jackets 57 6.3.5 Specimen Surface IrregularitiesError! Bookmark not defined. 57 6.3.6
27、Specimens for the Aging Tests 58 6.3.7 Calculation of Area of Test Specimens . 58 6.4 AGING TESTS . 59 6.4.1 Air Oven Aging Test 59 6.4.2 Oil Immersion Test 59 6.5 HEAT SHOCK TEST 59 6.6 COLD-BEND TEST 60 6.7 TIGHTNESS OF POLYETHYLENE JACKET TO SHEATH TEST 60 6.8 HOT CREEP TEST 60 ANSI/NEMA WC 70-20
28、09/ICEA S-95-658-2009 Page iii 2009 By the National Electrical Manufacturers Association And the Insulated Cable Engineers Association. 6.9 WRAP TEST FOR NYLON-COVERED INSULATED CONDUCTORS . 60 6.10 ELECTRICAL TESTS ON COMPLETED CABLES . 61 6.10.1 Voltage Tests . 61 6.10.2 Insulation Resistance 63 6
29、.10.3 Shield Continuity 63 6.11 RETESTS . 63 6.11.1 Physical and Aging Properties and Thickness 63 6.11.2 Other Tests 64 Section 7 QUALIFICATION TESTS . 65 7.0 GENERAL 65 7.1 ACCELERATED WATER ABSORPTION TEST, ELECTRICAL METHOD AT 60HZ . 65 7.2 Insulation Resistance Test . 65 7.3 TRAY CABLE FLAME TE
30、ST . 65 7.4 SUNLIGHT RESISTANCE TEST . 65 7.5 Halogen Content of Non-Metallic Elements . 65 7.6 Smoke generation test . 66 7.7 acid gas equivalent test 66 7.8 ENVIRONMENTAL STRESS CRACKING TEST 66 7.9 ABSORPTION COEFFICIENT 66 7.10 WET INSULATION RESISTANCE STABILITY TEST . 66 Section 8 CONSTRUCTION
31、S OF SPECIFIC TYPES 67 8.1 PREASSEMBLED AERIAL CABLES . 67 8.1.1 Scope . 67 8.1.2 Conductors 67 8.1.3 Insulation . 67 8.1.4 Jacket 67 8.1.5 Assembly . 67 8.1.6 Messenger . 67 8.1.7 Design Criteria . 67 APPENDICES . 68 APPENDIX A NEMA, ICEA, AND ASTM STANDARDS (Normative) . 68 APPENDIX B DEFINITIONS
32、OF MAXIMUM TEMPERATURES OF INSULATED CABLE CONDUCTORS (Normative) 71 APPENDIX C EMERGENCY OVERLOADS (Informative) . 72 APPENDIX D ABBREVIATIONS AND SYMBOLS (Informative) 73 APPENDIX E REPRESENTATIVE TENSILE STRENGTH AND ELONGATION OF NONMAGNETIC METALS (Informative) . 74 APPENDIX F RECOMMENDED BENDI
33、NG RADII FOR CABLES (Informative) . 75 APPENDIX G ADDITIONAL CONDUCTOR INFORMATION . 77 (Informative) 77 APPENDIX H PROCEDURE FOR DETERMINING DIMENSIONAL REQUIREMENTS OF JACKETS AND ASSOCIATED COVERINGS (Normative) 85 ANSI/NEMA WC 70-2009/ICEA S-95-658-2009 Page iv 2009 By the National Electrical Ma
34、nufacturers Association And the Insulated Cable Engineers Association. FOREWORD This Standards Publication for Power Cables Rated 2000 Volts or Less for the Distribution of Electrical Energy was developed by the Insulated Cable Engineers Association (ICEA) and approved by the National Electrical Man
35、ufacturers Association (NEMA). ICEA/NEMA Standards are adopted in the public interest and are designed to eliminate misunderstanding between the manufacturer and the user and to assist the user in selecting and obtaining the proper product for his particular need. Existence of an ICEA/NEMA Standard
36、does not in any respect preclude the manufacture or use of products not conforming to the standard. The user of this Standard is cautioned to observe any health or safety regulations and rules relative to the manufacture and use of cable made in conformity with this Standard. Requests for interpreta
37、tion of this Standard must be submitted in writing to: Insulated Cable Engineers Association, Inc. Post Office Box 1568 Carrollton, Georgia 30112 An official written interpretation will be provided once approved by ICEA and NEMA. Suggestions for improvements gained in the use of this Standard will b
38、e welcomed by the Association. ANSI/NEMA WC 70-2009/ICEA S-95-658-2009 Page 1 2009 By the National Electrical Manufacturers Association And the Insulated Cable Engineers Association. Section 1 GENERAL 1.1 SCOPE This standard applies to materials, constructions, and testing of 2000 volts and less the
39、rmoplastic, crosslinked polyethylene, and crosslinked rubber insulated wires and cables which are used for the transmission and distribution of electrical energy for normal conditions of installation and service, either indoors, outdoors, aerial, underground, or submarine. 1.2 GENERAL INFORMATION Th
40、is standard covers requirements for conductors, insulations and protective coverings and general constructional and dimensional details common to most standard types of wires and cables. Constructions of specific types are covered in Section 8 or in other ICEA standards. Where a conflict exists betw
41、een the requirements of Section 8, or other ICEA documents, and those of Sections 1 to 7 inclusive, the requirements of specific types shall apply. See Appendix A for complete titles and dates of ICEA publications and ASTM Standards to which reference is made in this publication. See Section 6 for t
42、est procedures not elsewhere referenced. Recommended minimum bending radii are given in Appendix F. In classifying crosslinked insulations and jackets in these standards, the term “rubber“ when used alone without further description shall mean synthetic rubber. Insulation thicknesses are designated
43、in terms of cable insulation levels (see 3.3). In classifying jackets and sheaths in these standards, the term “jacket“ refers to a continuous nonmetallic covering and “sheath“ to a continuous metallic covering. U.S. customary units, except for temperature, are specified throughout this standard. Ap
44、proximate International System of Units (SI) equivalents are included for information only. Requirements of a referenced ASTM standard shall be determined in accordance with the procedure or method designated in the referenced ASTM standard unless otherwise specified in this standard. 1.3 INFORMATIO
45、N TO BE SUPPLIED BY PURCHASER When requesting design proposals from cable manufacturers, the prospective purchaser should furnish the following information: 1.3.1 Characteristics of System on Which Cable is to be Used 1. Current - alternating or direct. 2. Frequency - Hertz. 3. Normal operating volt
46、age between phases or, in direct current, between conductors. 4. Number of phases and conductors. 5. Cable insulation level (see 3.2). 6. Minimum temperature at which cable will be installed. ANSI/NEMA WC 70-2009/ICEA S-95-658-2009 Page 2 2009 By the National Electrical Manufacturers Association And
47、 the Insulated Cable Engineers Association. 7. Description of installation. a. In buildings. b. In underground ducts. c. Aerial. (1) On messenger in metal rings. (2) Preassembled. (3) Field spun. d. Direct burial in ground. e. Submarine. f. Descriptions other than the foregoing. 8. Conditions of ins
48、tallation. a. Ambient temperature. b. Number of loaded cables in duct bank or conduit. For duct/conduit, give type of conduit (magnetic/nonmagnetic), size, number of loaded conduits, ducts enclosed or exposed, and spacing between duct/conduits. c. Load factor. d. Method of bonding and grounding of s
49、heaths. e. Wet or dry location. 9. Other special conditions. 1.3.2 Quantities and Description of Cable 1. Total number of feet, including test lengths, and shipping reel lengths if specific lengths are required. 2. Type of cable. Describe as single conductor, two-conductor, three-conductor, etc. 3. Rated circuit voltage, phase to phase. 4. Type of conductor - copper or aluminum. 5. Size of conductor If conditions require other than standard stranding, a complete description should be given. 6. Type of insulation. 7. Thickness of insulation. 8. Type of outer covering. 9. M
