1、NEMA Standards PublicationNational Electrical Manufacturers AssociationNEMA RV 2-2016Application and Installation Guidelines for Nonmetallic-Sheathed Cable and Underground Feeder and Branch Circuit CableNEMA RV 2-2016 Application and Installation Guidelines for Nonmetallic-Sheathed Cable and Undergr
2、ound Feeder and Branch Circuit Cable Published by: National Electrical Manufacturers Association 1300 North 17thStreet, Suite 900 Rosslyn, Virginia 22209 www.nema.org 2016 National Electrical Manufacturers Association. All rights including translation into other languages, reserved under the Univers
3、al Copyright Convention, the Berne Convention for the Protection of Literary and Artistic Works, and the International and Pan American Copyright Conventions. National Electrical Code(NEC) excerpts shown herein are reprinted with permission from NFPA 70-2017, NEC, 2016 National Fire Protection Assoc
4、iation, Quincy, Mass. This reprinted material is not the complete and official position of the NFPA on the referenced subject, which is represented only by the standard in its entirety. NOTICE AND DISCLAIMER The information in this publication was considered technically sound by the consensus of per
5、sons 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 this document. The National Electrical Manufacturers Association (NEMA) standards an
6、d guideline publications, of which the document contained herein is one, are developed through a voluntary consensus standards development process. This process brings together volunteers and/or seeks out the views of persons who have an interest in the topic covered by this publication. While NEMA
7、administers the process and establishes rules to promote fairness in the development of consensus, it does not write the document and it does not independently test, evaluate, or verify the accuracy or completeness of any information or the soundness of any judgments contained in its standards and g
8、uideline publications. NEMA disclaims liability for any 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 disc
9、laims 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 will fulfill any of your particular purposes or needs. NEMA does not undertake to guarantee
10、 the performance of any individual manufacturer or sellers products or services by virtue of this standard or guide. In publishing and making this document available, NEMA is not undertaking to render professional or other services for or on behalf of any person or entity, nor is NEMA undertaking to
11、 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 competent professional in determining the exercise of reasonable care in any given circumstances. Information and oth
12、er 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 publication. NEMA has no power, nor does it undertake to police or enforce compliance with the contents of this docume
13、nt. NEMA does 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 is solely the responsibility of the
14、certifier or maker of the statement. NEMA RV 2-2016 Page i 2016 National Electrical Manufacturers Association CONTENTS Foreword iii Section 1 Application Guidelines for Nonmetallic-Sheathed Cable 1 1.1 Construction. 1 1.1.1 General 1 1.1.2 Circuit Conductors . 1 1.1.3 Grounding Conductor 1 1.1.4 Cab
15、le Sheath . 1 1.2 Grounding 2 1.3 Marking and Identification 2 1.3.1 Finished Cable . 2 1.3.2 Grounding Conductors 2 1.3.3 Size Identification 2 1.4 Codes and Standards 2 1.4.1 National Electrical Code(NEC) . 2 1.4.1.1 Uses Permitted 2 1.4.1.2 Additional Permitted Uses of Type NM Cable 3 1.4.1.3 Use
16、s Not Permitted 3 1.4.1.4 Related NEC Articles 3 1.4.1.5 UL Certification Category Guide Information and Certifications on Website 5 Section 2 Application Guidelines for Underground Feeder and Branch Circuit Cable . 7 2.1 Construction. 7 2.1.1 General 7 2.1.2 Circuit Conductors . 7 2.1.3 Grounding C
17、onductors 7 2.1.4 Cable Sheath . 7 2.2 Grounding 8 2.3 Marking and Identification 8 2.3.1 Finished Cable . 8 2.3.2 Grounding Conductors 8 2.3.3 Jacket Color . 8 2.4 Codes and Standards 8 2.4.1 National Electrical Code(NEC) . 8 2.4.1.1 Uses Permitted 8 2.4.1.2 Uses Not Permitted 8 2.4.1.3 Additional
18、Information on the Use of UF Cables 9 2.4.1.3.1 Bending Radius 9 2.4.1.3.2 Ampacity 9 2.4.1.4 Related NEC Articles 9 2.4.2 UL Standards and Directories . 10 2.4.2.1 UL Standards 10 2.4.2.2 UL Directories 10 Section 3 Installation Guidelines for Nonmetallic-Sheathed Cable and Underground Feeder and B
19、ranch-Circuit Cable . 13 3.1 General 13 3.2 Inserting the Cable 13 3.3 Cable Preparation 13 3.4 Seating a Securement Clamp 13 3.5 Screw Tightening Torque 13 3.6 Supports 14 3.6.1 Required Intervals . 14 NEMA RV 2-2016 Page ii 2016 National Electrical Manufacturers Association 3.6.1.1 Type NM-B Cable
20、 14 3.6.1.2 Type UF-B Cable 14 3.6.2 Installation in Metal Framing Members . 14 3.6.3 Installation in Wood Framing Members . 14 3.7 Securing NM-B or UF-B at Nonmetallic Boxes Without Cable Clamps. 15 3.8 Underground Installations for UF-B . 15 3.9 Special Installation Considerations . 15 3.9.1 Expos
21、ed Work . 15 3.9.2 Unfinished Basements and Crawl Spaces 15 3.9.3 Accessible Attics 15 3.9.4 Corrosive Locations . 15 3.9.5 Solar Photovoltaic Systems . 15 3.10 Bending Radius . 16 3.11 Unsupported Cable 16 3.12 Ampacity 16 3.13 Damage . 16 3.13.1 Physical Damage . 16 3.13.2 Flood Damage . 16 3.14 V
22、erification of Installation . 16 TABLES 1-1 Grounding Conductors in NM-B Cables with 2, 3, or 4 Circuit Conductors 1 2-1 Grounding Conductors in UF-B Cables with 2, 3, or 4 Circuit Conductors . 7 FIGURES 1 Common Cable Support and Protection Product 18 2 Positioning Cables Under Staples . 19 NEMA RV
23、 2-2016 Page iii 2016 National Electrical Manufacturers Association Foreword These application and installation guidelines offer practical information on correct usage and industry-recommended practices for installation of Type NM-B nonmetallic-sheathed cable and Type UF-B underground feeder and bra
24、nch circuit cable in accordance with the National Electrical Code(NEC). These guidelines have been developed by the NEMA Building Wire and Cable Group and Dues Center, which has committed to periodically reviewing them for any revisions necessary to address changing conditions, product listing and i
25、nstallation requirements, and technical progress. Comments for proposed revisions are welcome and should be submitted to: Senior Technical Director, Operations National Electrical Manufacturers Association 1300 North 17thStreet, Suite 900 Rosslyn, Virginia 22209 At the time this document was approve
26、d, the Building Wire and Cable Group and Dues Center of the National Electrical Manufacturers Association (NEMA) had the following members: AFC Cable Systems, Inc., a part of Atkore Internationalhttp:/New Bedford, MA Cerro Wire LLChttp:/Hartselle, AL Colonial Wire Conduit Bodies; Fittings; and Handh
27、ole Enclosures 314.3 Nonmetallic Boxes 314.17 Conductors Entering Boxes, Conduit Bodies, or Fittings Article 334Nonmetallic-Sheathed Cable: Types NM, NMC, and NMS NEMA RV 2-2016 Page 4 2016 National Electrical Manufacturers Association Article 392Cable Trays 392.10 Uses Permitted Equipment for Gener
28、al Use Article 410Luminaires, Lampholders, and Lamps 410.24 Connection of Electric-Discharge and LED Luminaires Special Occupancies Article 518Assembly of Occupancies 518.4 Wiring Methods Article 520Theaters, Audience Areas of Motion Picture and TV Studios, Performance Areas, and Similar Locations 5
29、20.5(c) Wiring Methods Article 550Mobile Homes, Manufactured Homes, and Mobile Home Parks 550.15 Wiring Methods and Materials Article 551Recreational Vehicles and Recreational Vehicle Parks 551.47 Wiring Methods 551.55 Interior Equipment Grounding Article 552Park Trailers 552.48 Wiring Methods 552.5
30、6 Interior Equipment Grounding Special Conditions Article 725Class 1, Class 2, and Class 3 Remote-Control, Signaling, and Power-Limited Circuits 725.136 Separation from Electric Light, Power, Class 1, NPLFA Circuit Conductors and Medium Power Network-Powered Broadband Communication Cables Article 76
31、0.136 Separation from Electric Light, Power, Class 1, NPLFA and Medium Power Network-Powered Broadband Communications Circuit Conductors Communications Systems Article 800Communications Systems 800.133 Installation of Communications Wires, Cables, and Equipment Article 830Network-Powered Broadband C
32、ommunications Systems 830.133 Installation of Network-Powered Broadband Communications, Cables, and Equipment Reprinted with permission from NFPA 70-2017, National Electrical Code, 2016 National Fire Protection Association, Quincy, Mass. This reprinted material is not the referenced subject, which i
33、s represented only by the standard in its entirety. NEMA RV 2-2016 Page 5 2016 National Electrical Manufacturers Association 1.4.1.5 UL Certification Category Guide Information and Certifications on Website For each certification product category, UL publishes Guide Information that contains useful
34、information on the products that it lists, classifies, certifies and recognizes. The certification category guide information is frequently used by installers and by inspection authorities to gain a better understanding of how to specify and install products in accordance with their certification. T
35、his information is readily available on ULs Online Certifications Directory ( as well as UL Product Spec (http:/ The category should be chosen based on the information available to you. The key word or product type search is the easiest way to start if limited information is available. These website
36、s are helpful for locating the certification category guide information for products, as well as the certifications, and for understanding the details of how products (in this case, Type NM-B cable) are constructed and marked. Information on special or optional ratings and terminations is also avail
37、able. The certification category guide information for Nonmetallic-sheathed Cable, PWVX is reprinted below. The UL Fire Resistance Directory covers UL-certified methods for maintaining the Fire Resistive Rating on walls, floors, and ceilings for fire resistancerated construction when cables must pen
38、etrate them and be firestopped. The following information on Type NM-B cable is reprinted from the Online Certifications Directory with permission from UL 2017 UL LLC: Nonmetallic-sheathed Cable, PWVX USE This category covers Types NM-B and NMC-B nonmetallic-sheathed cable, rated 600 V, intended for
39、 use in accordance with Article 334 of ANSI/NFPA 70, “National Electrical Code” (NEC), and certified in copper sizes 14 to 2 AWG inclusive and aluminum or copper-clad aluminum sizes 12 to 2 AWG inclusive. This cable contains conductors rated 90C; however, the ampacities of the cable are those of 60C
40、 conductors as specified in Article 334 and Table 310.15(B)(16) of the NEC. PRODUCT MARKINGS Cable with copper-clad aluminum conductors is surface marked “AL (CU-CLAD)“ or “Cu-clad Al,“ and cable with aluminum conductors is surface marked “AL.“ Wire and cable employing compact-stranded copper conduc
41、tors is so identified directly following the conductor size, wherever it appears (surface, tag, carton or reel), by “compact copper.” The abbreviations “CMPCT” and “CU” may be used for compact and copper, respectively. Tags, reels and cartons for products employing compact-stranded copper conductors
42、 have the marking: “Terminate with connectors identified for use with compact-stranded copper conductors.” Cable suitable for use in cable trays is appropriately marked. Cable marked for cable tray use may also have a supplementary sunlight resistant marking. Cable that complies with the Limited Smo
43、ke Test requirements specified in UL 1685, “Vertical-Tray Fire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables,” is surface marked “ST1.” PRODUCT IDENTITY One of the following product identities appears on the product: Nonmetallic-sheathed Aluminum Cable (for nonmetallic-s
44、heathed cable that contains aluminum conductors) NEMA RV 2-2016 Page 6 2016 National Electrical Manufacturers Association Nonmetallic-sheathed Cable (for nonmetallic-sheathed cable that contains copper or copper-clad aluminum conductors) ADDITIONAL INFORMATION For additional information, see Electri
45、cal Equipment for Use in Ordinary Locations (AALZ). REQUIREMENTS The basic standard used to investigate products in this category is ANSI/UL 719, “Nonmetallic-Sheathed Cables.” UL MARK The UL symbol on the product and the Certification Mark of UL on the attached tag, coil, reel, or on the smallest u
46、nit container in which the product is packaged is the only method provided by UL to identify products manufactured under its Certification and Follow-Up Service. The Certification Mark for these products includes the UL symbol, the words “CERTIFIED” and “SAFETY,” the geographic identifier(s), and a
47、file number. Alternate UL Mark The UL symbol on the product and the Listing Mark of UL on the attached tag, coil, reel or smallest unit container in which the product is packaged is the only method provided by UL to identify these products manufactured under its Listing and Follow-Up Service. The Li
48、sting Mark for these products includes the UL symbol (as illustrated in the Introduction of this Directory) together with the word “LISTED,” a control number, and the product name as appropriate: Nonmetallic-sheathed cable that contains copper or copper-clad aluminum conductors has the product name
49、“Nonmetallic-sheathed Cable”; nonmetallic-sheathed cable that contains aluminum conductors has the product name “Nonmetallic-sheathed Aluminum Cable.” UL Fire Resistance Directory, The Orange Book ULs Fire Resistance Directory generally covers the construction detail necessary for constructing fire-rated walls, floors, and ceilings. It also covers the certified materials and methods for sealing the wall, ceiling, or floor that has
