NEMA WC 71-2014 Nonshielded Cables Rated 2001-5000 V for Use in the Distribution of Electric Energy (JOINT PUBLICATION - NEMA WC 71 ICEA S-96-659).pdf

1、NEMA Standards PublicationNational Electrical Manufacturers AssociationANSI/NEMA WC 71-2014Nonshielded Cables Rated 2001-5000 V forUse in the Distribution of Electric EnergyApproved as an American National Standard ANSI Approval Date: June 10, 2014 ANSI/NEMA WC 71 ICEA S-96-659-2014 Nonshielded Cabl

2、es Rated 2001-5000 V for Use in the Distribution of Electric Energy Prepared by: Insulated Cable Engineers Association, Inc. P.O. Box 1568 Carrollton, Georgia 30112 Published by: National Electrical Manufacturers Association 1300 North 17thStreet, Suite 900 Rosslyn, Virginia 22209 www.nema.org 2014

3、National Electrical Manufactures Association and the Insulated Cable Engineers Association, Inc. 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 an

4、d Pan American copyright conventions. 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Association, Inc. NOTICE AND DISCLAIMER The information in this publication was considered technically sound by the consensus of persons engaged in the development and approval

5、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 this document. The National Electrical Manufacturers Association (NEMA) and the Insulated Cable Engineers Association, Inc. (ICEA

6、) standards and guideline publications, of which the document contained herein is one, are developed through a voluntary consensus standards development process. This process brings together persons who have an interest in the topic covered by this publication. While NEMA and ICEA administer the pro

7、cess and establish rules to promote fairness in the development of consensus, they do not independently test, evaluate, or verify the accuracy or completeness of any information or the soundness of any judgments contained in their standards and guideline publications. NEMA and ICEA disclaim liabilit

8、y for personal injury, property, or other damages of any nature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, application, or reliance on this document. NEMA and ICEA disclaim and make no guaranty or warranty, ex

9、pressed or implied, as to the accuracy or completeness of any information published herein, and disclaim and make no warranty that the information in this document will fulfill any of your particular purposes or needs. NEMA and ICEA do not undertake to guarantee the performance of any individual man

10、ufacturers 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 to render professional or other services for or on behalf of any person or entity, nor are NEMA and ICEA undertaking to perform any duty

11、 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 competent professional in determining the exercise of reasonable care in any given circumstances. Information and other standards on t

12、he 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 publication. NEMA and ICEA have no power, nor do they undertake to police or enforce compliance with the contents of this document. NEM

13、A 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 any health- or safety-related information in this document shall not be attributable to NEMA and ICEA and is solely the responsibilit

14、y of the certifier or maker of the statement.ANSI/NEMA WC 71/ICEA S-96-659-2014 Page i 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Association, Inc. Foreword This standards publication, Standard for Nonshielded Cables Rated 2001-5000 Volts for Use in the Dist

15、ribution of Electric Energy, was developed by the Insulated Cable Engineers Association, Inc. (ICEA) and approved by the National Electrical Manufacturers Association (NEMA). ICEA/NEMA standards are adopted in the public interest and are designed to eliminate misunderstandings between the manufactur

16、ers and the user and to assist the user in selecting and obtaining the proper product for his or her particular need. The user of this standards publication is cautioned to observe any health or safety regulations and rules relative to the use of cable made in conformity with this standard. Requests

17、 for interpretation of this standard must be submitted in writing to: Insulated Cable Engineers Association, Inc. P.O. Box 1568 Carrollton, GA 30112 An official interpretation will be made by the association. Suggestions for improvements in this publication are welcome, and should be sent to ICEA a

18、t the above address. The following members of the ICEA working group contributed to the writing of this standard: R. E. Fleming, Chairman J. Armstrong E. Bartolucci M. Bodziony R. Bristol J. Cancelosi F. Clark W. Crawford A. Davila D. Farrick M. Fuller F. Kuchta M. Levitre P-M. Leblanc K. Nuckles H.

19、 Soleski C. Spradlin R. Szilagyi B. Vaughn E. Walcott R. Williamson R. Young ANSI/NEMA WC 71/ICEA S-96-659-2014 Page ii 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Association, Inc. Contents Foreword i Section 1 General 1 1.1 SCOPE 1 1.2 GENERAL INFORMATION .

20、 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 Descriptions of Cable 2 1.4 DEFINITIONS AND SYMBOLS 2 Section 2 Conductors . 6 2.0 GENERAL . 6 2.1 PHYSICAL AND ELECTRICAL PROPERTIES 6 2.1.1 Copper Conductors 6 2

21、.1.2 Aluminum Conductors . 6 2.2 OPTIONAL SEALANT FOR STRANDED CONDUCTORS 7 2.3 CONDUCTOR SIZE UNITS 7 2.4 CONDUCTOR DC RESISTANCE 7 2.4.1 Direct Measurement of DC Resistance . 7 2.4.2 Calculation of DC Resistance 7 2.5 CONDUCTOR DIAMETER . 8 Section 3 Stress Control Layer (Conductor Shield) . 14 3.

22、0 GENERAL . 14 3.1 MATERIAL AND THICKNESS 14 3.2 PHYSICAL REQUIREMENTS 14 3.3 ELECTRICAL REQUIREMENTS 15 3.3.1 Extruded Semiconducting Material 15 3.3.2 Semiconducting Tape 15 3.3.3 Extruded Nonconducting Material (for EPR Insulation Only) . 15 3.4 CROSSLINKED (THERMOSET) REQUIREMENTS 15 Section 4 I

23、nsulation. 16 4.1 INSULATION MATERIALS . 16 4.2 INSULATION LEVELS 16 4.3 INSULATION AND JACKET THICKNESSES. 17 4.3.1 Three-Phase Systems With 100% or 133% Insulation Level 17 4.3.2 Delta Systems Where One Phase May Be Grounded for More Than One Hour 17 4.3.3 Single- and Two-Phase Systems With 100% A

24、nd 133% Insulation Level 17 4.3.4 Direct-Current Systems . 17 4.4 INSULATION REQUIREMENTS 18 4.4.1 Voltage Tests . 18 4.4.2 Insulation Resistance . 18 ANSI/NEMA WC 71/ICEA S-96-659-2014 Page iii 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Association, Inc. 4.

25、4.3 Other Requirements 18 Section 5 Coverings 21 5.1 JACKETS 21 5.1.1 Crosslinked and Thermoplastic Jackets 21 5.1.2 Neoprene, Heavy-duty Black (CR-HD) 21 5.1.3 Neoprene, General Purpose (CR-GP) . 21 5.1.4 Polyvinyl Chloride (PVC) 21 5.1.5 Low and Linear Low-density Polyethylene (LDPE left-hand lay

26、is a counterclockwise twist away from the observer. Lay Length The lay of any helical element of a cable is the axial length of one turn of a helix of that element Lot (cable) The quantity of cable requiring one test Lot (material) A quantity of material used in cable construction that is produced a

27、t the same location under the same manufacturing conditions during the same time period ANSI/NEMA WC 71/ICEA S-96-659-2014 Page 4 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Association, Inc. Master Length A continuous length of cable collected on a reel at t

28、he end of an extrusion line Maximum Rated Conductor Temperatures: Normal The highest conductor temperature permissible for any part of the cable Operating line under normal operating current load Emergency The highest conductor temperature permissible for any part of the cable line Overload during e

29、mergency overload of specified time, magnitude, and frequency of application Short The highest conductor temperature permissible for any part of the cable line Circuit during a circuit fault of specified time and magnitude Nominal Value The value by which a quantity is designated and often used in t

30、ables (taking into account specified tolerances) but does not require testing or measurement for verification Pitch Diameter The core diameter plus half the buildup of the layer being considered. The pitch diameter of a single layer of armor wires, for example, is equal to the diameter under the wir

31、es plus twice one half the diameter of one wire. Power Frequency A voltage frequency between 49 and 61 Hz Production Tests Tests defined in Part 7 of this standard with specific test frequency Qualification Tests Tests defined in Part 8 of this standard with specific test frequency Room Temperature

32、25 5C air temperature (RT) Sheath A continuous metallic covering Shipping Length A completed length of cable that has passed all test requirements. It might or might not be cut into shorter lengths before it is supplied to the end-use customer. Shipping Reel A completed reel of cable shipped to the

33、end use customer Thermoplastic A polymeric material that repeatedly can be softened by heating and hardened by cooling through a temperature range characteristic of the material and which, in softened state, can be shaped through the application of force Thermoset A polymeric material that, when cro

34、sslinked, will not flow on subsequent heating. Crosslinking is accomplished chemically or by irradiation. Tree-retardant A tree-retardant crosslinked polyethylene (TRXLPE) insulation compound XLPE Insulation based on XLPE, containing an additive, a polymer modification, or filler that retards the de

35、velopment and growth of water trees in the insulation compound Unfilled Crosslinked XLPE insulation containing less than 10% mineral filler by weight Polyethylene ANSI/NEMA WC 71/ICEA S-96-659-2014 Page 5 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Associatio

36、n, Inc. V phase-to-phase voltage Vgphase-to-ground voltage Water Blocking A nonmetallic material incorporated in a cable construction intended as an Component impediment to water penetration. A water-blocking component can be a pumpable or extrudable conductor filler compound; a water-swellable tape

37、, yarn, or powder; or a combination thereof. XLPE Insulation Crosslinked polyethylene insulation ANSI/NEMA WC 71/ICEA S-96-659-2014 Page 6 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Association, Inc. Section 2 CONDUCTORS 2.0 GENERAL Conductors shall meet the

38、 requirements of the appropriate ASTM standards referenced in 2.1, except that compliance with cross-sectional area is not required. Resistance will be determined in accordance with 2.4, and diameters will be in accordance with 2.5. The following technical information on typical conductors can be fo

39、und in Appendix G: a) Approximate diameters of individual wires in stranded conductors. b) Approximate conductor weights. 2.1 PHYSICAL AND ELECTRICAL PROPERTIES The conductors used in the cable shall be copper, in accordance with 2.1.1, or aluminum, in accordance with 2.1.2, as applicable, except as

40、 noted in 2.0. Conductors shall be solid or stranded. The outer layer of an uncoated stranded copper conductor may be tin-coated to obtain free stripping of an adjacent polymeric layer. Other stranding available by agreement between purchaser and manufacturer. 2.1.1 Copper Conductors a) ASTM B 3 for

41、 Soft or Annealed Uncoated Copper b) ASTM B 5 for Electrical Grade Copper c) ASTM B 8 for Class A, B, C, or D Stranded Copper Conductors d) ASTM B 33 for Soft or Annealed Tin-coated Copper Wire e) ASTM B 496 for Compact Round Stranded Copper Conductors f) ASTM B 784 for Modified Concentric-lay Stran

42、ded Copper Conductors g) ASTM B 787 for 19 Wire Combination Unilay-stranded Copper Conductors h) ASTM B 835 for Compact Round Stranded Copper Conductors Using Single-input Wire Constructions i) ASTM B 902 for Compressed Round Stranded Copper Conductors, Hard, Medium-Hard, or Soft Using Single-input

43、Wire Constructions 2.1.2 Aluminum Conductors a) ASTM B 230 for Electrical Grade Aluminum 1350-H19 b) ASTM B 231 for Class A, B, C, or D Stranded Aluminum 1350 Conductors c) ASTM B 233 for Electrical Grade Aluminum 1350 Drawing Stock d) ASTM B 400 for Compact Round Stranded Aluminum 1350 Conductors e

44、) ASTM B 609 for Electrical Grade Aluminum 1350 Annealed and Intermediate Tempers f) ASTM B 786 for 19 Wire Combination Unilay-stranded Aluminum 1350 Conductors g) ASTM B 800 for 8000 Series Aluminum Alloy Annealed and Intermediate Tempers h) ASTM B 801 for 8000 Series Aluminum Alloy Wires, Compact

45、Round, Compressed, and Concentric-lay Class A, B, C, and D Stranded Conductors i) ASTM B 836 for Compact Round Stranded Aluminum Conductors Using Single-input Wire Constructions j) ASTM B 901 for Compressed Round Stranded Aluminum Conductors Using Single-input Wire Construction ANSI/NEMA WC 71/ICEA

46、S-96-659-2014 Page 7 2014 National Electrical Manufacturers Association and the Insulated Cable Engineers Association, Inc. 2.2 OPTIONAL SEALANT FOR STRANDED CONDUCTORS With the approval of the purchaser, a sealant designed as an impediment to longitudinal water penetration may be incorporated in th

47、e interstices of the stranded conductor. Compatibility with the conductor shield shall be determined in accordance with ICEA T-32-645. Longitudinal water penetration resistance shall be determined in accordance with ICEA Publication T-31-610 and shall meet a minimum requirement of 5 psig (34.5 kPa).

48、 2.3 CONDUCTOR SIZE UNITS Conductor size shall be expressed by cross-sectional area in units of one-thousand circular mils (kcmil). The AWG equivalents for small conductor sizes are found in Table 2-4. The metric equivalents for all sizes are found in Table 2-4 (Metric). 2.4 CONDUCTOR DC RESISTANCE

49、The DC resistance of each conductor in a production or shipping length of completed cable shall not exceed the value determined from the schedule of maximum DC resistances specified in Table 2-2, when using the appropriate nominal value specified in Table 2-3 or Table 2-3 (Metric). The DC resistance shall be determined in accordance with 2.4.1. Nominal DC resistance is calculated in accordance with 2.4.2. Table 2-3 shows nominal resistance for standard conductor sizes. Where the outer layer of an otherwise uncoated stranded copper