NEMA RV 1-2016 Application and Installation Guidelines for Armored Cable and Metal-Clad Cable.pdf

1、NEMA Standards PublicationNational Electrical Manufacturers AssociationNEMA RV 1-2016Application and Installation Guidelines for Armored Cable and Metal-Clad CableNEMA Standards Publication RV 1-2016 Application and Installation Guidelines for Armored Cable and Metal-Clad Cable Published by: Nationa

2、l Electrical Manufacturers Association 1300 North 17th Street, Suite 900 Rosslyn, VA 22209 www.nema.org 2016 National Electrical Manufacturers Association. All rights, including translation into other languages, reserved under the Universal Copyright Convention, the Berne Convention for the Protecti

3、on of Literary and Artistic Works, and the International and Pan American copyright conventions. The NEC excerpts shown herein are reprinted with permission from NFPA 70-2017, National Electrical Code, 2016, National Fire Protection Association, Quincy, MA. This reprinted material is not the complet

4、e and official position of the NFPA on the referenced subject, which is represented only by the standard in its entirety. 2016 National Electrical Manufacturers Association NOTICE AND DISCLAIMER The information in this publication was considered technically sound by a consensus among persons engaged

5、 in its development at the time it was approved. Consensus does not necessarily mean there was unanimous agreement among every person participating in the development process. The National Electrical Manufacturers Association (NEMA) standards and guideline publications, of which the document herein

6、is one, are developed through a voluntary 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. Although NEMA administers the process and establishes rules to promote fairness in the

7、 development of consensus, it does not write the documents, nor does it independently test, evaluate, or verify the accuracy or completeness of any information or the soundness of any judgments contained in its standards and guideline publications. NEMA disclaims liability for any personal injury, p

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9、mpleteness of any information published herein, and disclaims and makes no warranty that the information in this document will fulfill any particular purpose(s) or need(s). NEMA does not undertake to guarantee the performance of any individual manufacturers or sellers products or services by virtue

10、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 perform any duty owed by any person or entity to someone else. Anyone using this document

11、 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 circumstance. Information and other standards on the topic covered by this publication may be available from other sources,

12、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 document. NEMA does not certify, test, or inspect products, designs, or installations for safety

13、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 certifier or maker of the statement. NEMA RV 1-2016 Page i 2016 National Electrical Manufac

14、turers Association FOREWORD These application and installation guidelines offer practical information on correct application and industry-recommended practices for the installation of armored cable (Type AC) and metal-clad cable (Type MC) in accordance with the National Electrical Code(NEC). These g

15、uidelines were developed by the NEMA Building Wire and Cable section, which has committed to periodically reviewing them for any revisions necessary to address changing conditions, product listing and installation requirements, and technical progress. Comments for proposed revisions are welcomed and

16、 should be submitted to: Senior Technical Director, Operations National Electrical Manufacturers Association 1300 N. 17thStreet, Suite 900 Rosslyn, VA 22209 At the time of approval, the NEMA Building Wire and Cable Group had the following members: AFC Cable Systems, Inc., a part of Atkore Internatio

17、nal New Bedford, MA Anamet Electrical, Inc. Mattoon, IL Cerro Wire LLC Hartselle, AL Colonial Wire they only provide guidance on where and how the cable may be used. The following provides additional guidance on the uses of Type AC cable: General A key provision of the permitted uses of Type AC is t

18、hat Type AC cable is required to comply with all applicable sections of the NEC. While 320.10 permits Type AC to be used as branch circuits and feeders, other NEC articles that apply to the particular installation must be reviewed to determine if additional requirements or restrictions apply. For ex

19、ample, 517.13(A) permits Type AC cable for use in patient care areas of healthcare facilities. However, in accordance with 517.13(B), the cable must contain an insulated equipment grounding conductor. Where Not Subject to Physical Damage Type AC cable must be protected from physical damage. This inc

20、ludes installing the cable at heights and locations where the cable will not be exposed to damage. It also includes providing mechanical protection for the cable from nails and screws in accordance with 300.4(D) by maintaining a 1-1/4 in. (32 mm) distance from the edge of a framing member, or by pro

21、viding a metal plate where the distance cannot be maintained from the edge of a framing member or a furring strip. In Both Exposed and Concealed Installations Type AC cable is permitted for installation in both exposed and concealed work; however, the cable must be protected from physical damage. Ex

22、posed work includes installations above suspended ceilings where installed behind panels designed to allow access. Where installed above suspended ceilings, 300.11 should be consulted for requirements for securing and supporting the cable. In Cable Tray All UL Listed Type AC cable is acceptable for

23、use in cable tray. There is no marking on the cable that indicates that the cable is identified for such use because the metallic armor enables the cable to meet the flame requirements for cable installed in cable tray. If documentation is required to show that Type AC is identified for use in cable

24、 tray, ULs Guide Information for Electrical Equipment (White Book) contains the necessary information. NEC Article 392 should be consulted for cable tray installation requirements. In Dry Locations Type AC cable is rated only for dry locations. The insulation used is not suitable for wet locations.

25、The cable is permitted a limited exposure during building construction as defined in Article 100 under dry locations: A dry location is a location not normally subject to dampness or wetness. A location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building

26、 under construction. In addition to permitted uses covered in 320.10, Type AC is permitted for installation as follows: 1) In other spaces used for environmental air (plenums) in accordance with section 300.22(C); 2) Under raised floors of computer rooms in accordance with section 645.5(E); NEMA RV

27、1-2016 Page 4 2016 National Electrical Manufacturers Association 3) In patient care spaces of health care facilities, hospitals, and nursing homes in accordance with section 517.13(A) and (B) where an insulated equipment grounding conductor is used; 4) In essential electrical systems for hospitals i

28、n accordance with 517.31(C)(3)(3) under the installation conditions described in 517.31(C)(3)(3) a-f. 5) Isolated or dedicated ground circuits where an insulated equipment grounding conductor is used; 6) Lighting whips; and, 7) Motor leads. Based on the limitations of its construction, limited size

29、range, number of conductors, and absence of an optional outer nonmetallic jacket, Type AC cable is typically used as part of branch circuit wiring in multi-family residential/commercial and institutional applications. Industrial installations typically use Type MC cable, which does not have these li

30、mitations. 1.4.1.2 Uses Not Permitted As with permitted uses, those uses not permitted by the NEC are not all-inclusive. The codes language is intended to provide guidance on where and how the cable may be used. NEC 320.12 specifies the uses of Type AC that are not permitted, which are as follows: 1

31、) Where subject to physical damage 2) In damp or wet locations 3) In air voids of masonry block or tile walls where such walls are exposed or subject to excessive moisture or dampness. 4) Where exposed to corrosive conditions 5) Embedded in plaster finish on brick or other masonry in damp or wet loc

32、ations A review of the uses not permitted shows a central theme that Type AC cable is not permitted where corrosive environments may be present or in wet or damp locations. For installations where a corrosive environment exists, a cable with a protective outer covering, such as Type MC with an outer

33、 nonmetallic jacket, should be used. Similarly, in a wet or damp location, Type MC with wet-rated conductors should be used. 1.4.1.3 Related NEC Articles The following NEC articles also contain provisions for the use of Type AC: Chapter 2: Wiring and Protection Article 250 Grounding and Bonding 250.

34、118(8) Use of the Armor of Type AC as Equipment Grounding Conductor Chapter 3: Wiring Methods and Materials Article 300 General Requirements for Wiring Methods and Materials 300.15 Boxes, Conduit Bodies, or FittingsWhere Required 300.16 Raceway or Cable to Open or Concealed Wiring 300.22(C)(1) Wirin

35、g Methods (in Plenums) Article 310 Conductors for General Wiring 310.15 Ampacities for Conductors rated 02000 Volts 310.120 Marking Article 320 Armored Cable: Type AC Article 392 Cable Trays 392.10(A) Wiring Methods NEMA RV 1-2016 Page 5 2016 National Electrical Manufacturers Association Chapter 4:

36、Equipment for General Use Article 410 Luminaires, Lampholders, and Lamps 410.24 Connection of Electric-Discharge and LED Luminaires 410.117(C) Tap Conductors Article 430 Motors, Motor Circuits, and Controllers 430.245 Method of Grounding Chapter 5: Special Occupancies Article 517 Health Care Facilit

37、ies 517.13(A) Wiring Methods (Patient Care Area Grounding) 517.30(C)(3)(3) Mechanical Protection of the Essential Electrical System Article 518 Assembly Occupancies 518.4 Wiring Methods Article 520 Theaters, Audience Areas of Motion Picture and Television Studios, Performance Areas, and Similar Loca

38、tions 520.5 Wiring Methods Article 530 Motion Picture and Television Studios and Similar Locations 530.11 Permanent Wiring Article 550 Mobile Homes, Manufactured Homes, and Mobile Home Parks 550.16(A)(2) Connections of Ranges and Clothes Dryers Article 551 Recreational Vehicles and Recreational Vehi

39、cle Parks 551.47(G) Wiring Methods-Protected 551.55(C) Interior Equipment Grounding Article 552 Park Trailers 552.48 Wiring Methods 552.56(C)(1) Interior Equipment Grounding Chapter 6: Special Equipment Article 604 Manufactured Wiring Systems Article 605 Office Furnishings Article 610 Cranes and Hoi

40、sts 610.11 Wiring Method Article 620 Elevators, Dumbwaiters, Escalators, Moving Walks, Platform Lifts, and Stairway Chairlifts 620.21 Wiring Methods 620.81 Metal Raceways Attached to Cars Article 645 Information Technology Equipment 645.5 Supply Circuits and Interconnecting Cables Article 668 Electr

41、olytic Cells 668.30(C) Fixed and Portable Electrical EquipmentWiring Methods Article 680 Swimming Pools, Fountains, and Similar Installations Article 690 Solar Photovoltaic (PV) Systems Reprinted with permission from NFPA 70-2017, the National Electrical Code, 2016, National Fire Protection Associat

42、ion, Quincy, MA 02269. This reprinted material is not the referenced subject, which is represented only by the standard in its entirety. 1.4.2 Underwriters Laboratories (UL) Standards and Certification Category Guide Information UL publishes a number of standards and certification category guide inf

43、ormation that provide detailed information on the construction, performance, application, ratings, and installation aspects of Type AC cable. NEMA RV 1-2016 Page 6 2016 National Electrical Manufacturers Association 1.4.2.1 UL Standards The UL standard for the construction and performance of Type AC

44、cable is UL 4. According to NEC 320.104, the insulated conductors for Type AC cable must be of the types listed in Table 310.104(A) or one identified for use in this cable. Practically all Type AC cable contains Type THHN, a thermoplastic-insulated conductor covered in UL 83. Insulation types, howev

45、er, could be a thermosetting type such as Type XHH or RHH conductors covered in UL 44. 1.4.2.2 UL Certification Category Guide Information and Certifications on Website UL publishes Guide Information for each certification product category that contains useful information on the products that it lis

46、ts, classifies, certifies, and recognizes. The certification category guide information is frequently used by installers and inspection authorities to gain a better understanding of how to specify and install products in accordance with their certifications. All of this information is readily availa

47、ble on ULs Online Certifications Directory ( and UL Product Spec ( The category should be chosen based on the information available. The keyword or product type search is the easiest way to start if limited information is available. These websites are helpful tools for locating the certification cat

48、egory Guide Information for products; understanding the details of how products, in this case Type AC cable, are constructed and marked; and obtaining information on special or optional ratings as well as terminations. The certification category Guide Information for Armored Cable (AWEZ) is reprinte

49、d below. The UL Fire Resistance Directory covers the UL certified methods for maintaining the fire-resistive rating on walls, floors, and ceilings for fire-resistive-rated construction, when cable must penetrate them and be fire-stopped. The following information on Type AC cable is reprinted from the Online Certifications Directory with permission from UL 2017 UL LLC: Armored Cable (AWEZ) GENERAL This category covers armored cable in sizes 14-1 AWG copper and 12-1 AWG aluminum or copper-clad aluminum and rated 600 V or les