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2005 NEC Changes Summary Articles 800 through 830a

Chapter 8 Communications Systems

Please Note: No figures / illustrations are included with this article

Chapter 8 of the National Electrical Code covers the wiring requirements for communications systems such as telephones, radio and TV antennas, satellite dishes, closed-circuit television (CCTV), and cable TV (CATV) systems, as well as network-powered broadband communications systems, not under the exclusive control of the communications utility. Figure 800-1

Communications systems aren't subject to the general requirements contained in Chapters 1 through 4 or the special requirements of Chapters 5 through 7, except where there's a specific reference in Chapter 8 to a rule in one of those chapters [90.3], Figure 800-2

Also, installations of communications equipment under the exclusive control of communications utilities located outdoors, or in building spaces used exclusively for such installations, are exempt from the NEC [90.2(B)(4)].

ARTICLE 800 Communications Circuits

This article has its roots in telephone technology. Consequently, it addresses telephone and related systems that use twisted-pair wiring. Here are a few key points to remember from Article 800:

  • Don't attach incoming cables to the service entrance power mast.
  • It is critical to determine the "point of entrance" for these circuits.
  • You must ground the primary protector as close as practicable to the point of entrance.
  • Keep the grounding conductor for the primary protector as straight and as short as possible.
  • If you locate cables above a suspended ceiling, route and support them to allow access via panel removal.
  • Keep these cables separated from lightning-protection circuits.
  • If you install cables in a Chapter 3 raceway, you must do so in conformance with the NEC requirements for the raceway system.
  • Special labeling and marking provisions apply-follow them carefully.
  • Text revised to specify that the accessible portion of communications cables must be removed.
  • New FPN alerts the Code user to a comprehensive standard that identifies what "installed in a neat and workmanlike manner" means. And section revised to specify that communications cables must be secured in place and that the ceiling support wires or ceiling grid must not be used for this purpose in accordance with 300.11.
  • New FPN alerts the Code user that limiting the length of the grounding conductor for the primary protector should reduce voltages that may develop between the building's power and communications systems during a lightning event.

Article 810. Radio and Television Equipment

This article has its roots in communications. Consequently, it addresses transmitter and receiver equipment-and wiring and cabling associated with that equipment. Here are a few key points to remember from Article 810:

  • Avoid contact with conductors of other systems.
  • Don't attach antennas or other equipment to the service entrance power mast.
  • If you do not ground the mast properly, voltage surges caused by nearby lightning strikes could destroy it.
  • Keep the grounding conductor straight, and protect it from physical damage.
  • If you do not bond the mast properly, you risk flashovers and possible electrocution.
  • Keep in mind that the purpose of bonding is to prevent a difference of potential between metallic objects and other conductive items, such as swimming pools. Thus, Article 810 provides several different bonding requirements.
  • Clearances are critical. Article 810 provides extensive clearance requirements. For example, it provides separate clearance requirements for indoor and outdoor locations.
  • New subsection clarifies the type of grounding electrode termination fitting that is suitable for the discharge-unit grounding conductor.

Article 820. Community Antenna Television (CATV) and Radio Distribution Systems

This article focuses on the distribution of television and radio signals within a facility or on a property via cable, rather than their transmission or reception via antenna. These signals are limited-energy, but they are high frequency.

  • As with Article 800, you must determine the "point of entrance" for these circuits.
  • You must ground the incoming cable as close as practicable to the point of entrance.
  • If you locate cables above a suspended ceiling, route and support them to allow access via panel removal.
  • Clearances are critical. Article 820 provides extensive clearance requirements. For example, Article 820 requires at least 6 ft of clearance between coaxial cable and lightning conductors.
  • If you use a separate grounding electrode, you must run a bonding jumper to the power grounding system.
  • Text revised to clarify that the accessible portion of abandoned coaxial cables must be removed.
  • New FPN alerts the Code user to a comprehensive standard that identifies what "installed in a neat and workmanlike manner" means. And section revised to that CATV cables must be secured in place and that the ceiling support wires or ceiling grid must not be used for this purpose.
  • New FPN alerts the Code user that limiting the length of the grounding conductor should reduce voltages that may develop between the building's power and communications systems during a lightning event.
  • New subsections added to recognize the use of raceways designed for coaxial cables.

ARTICLE 830 Network-Powered Broadband Communications Systems

Article 830 contains the installation requirements for network-powered broadband communications circuits that provide voice, audio, video, data, and interactive services through a network interface unit (NIU) [820.2].

FPN No. 1: A typical network-powered broadband system includes a cable supplying power and broadband signal to a network interface unit that converts the broadband signal into voice, audio, video, data, and interactive services signals. Figure 830-1

FPN No. 2: The installation requirements contained in Article 830 only apply to the circuit that extends from the communications utility to the network interface unit (NIU) at the premises, when not under the exclusive control of the communications utility [90.2(B)(4)]. Figure 830-2

Author's Comment: Since the network-powered broadband circuit terminates at the exterior of a building and it is under the exclusive control of the communications utility, there's no need for this subject to be covered in this textbook. However, the output wiring (voice, audio, video, data, and interactive services signals) from the network interface unit must be installed in accordance with the following article [830.3(D)]:

  • Article 725 for Class 2 and Class 3 circuits
  • Article 760 for power-limited fire alarm circuits
  • Article 770 for optical fiber cables
  • Article 800 for communications circuits
  • Article 820 for community antenna television and radio distribution circuits

Mike Holt's Comment: If you desire more information about any of the above changes, be sure to order my Changes book below and/or library (Video/DVD).

12a. NEC Code Changes Textbook
Mike Holt’s Illustrated Changes to the NEC 2005 textbook is here! So, get ready now!

The 2005 NEC is here and its time to adapt. Don’t let the scale of this change intimidate you. With Mike Holt’s Illustrated Changes to the NEC 2005, you’ll be up-to-speed in no time. Nearly 5,000 changes were proposed for the 2005 NEC! Over 225 of them will have a significant impact on designing, installing and inspecting electrical systems. Mike takes you through these changes, which he considers to be of critical importance. You’ll be able to easily gauge how these changes will impact your work and apply them instantly. This 120-page comprehensive full-color textbook includes 198 color illustrations for reference. Subjects include: General Requirements, Circuits and Protection, Grounding versus Bonding, Wiring Methods, Equipment for General Use, Special Occupancies, Special Equipment, Special Conditions, and Limited Energy and Communications Systems.

Why does Mike’s book give you an edge? Because of the extra effort put forth to organize these changes in an easy-to-follow manner. Each change includes:

  • Cross references to other related Code requirements to help you develop a better understanding of how the Code rules relate to one another.
  • Background information for each change along with explanations, which are delivered in Mike’s trademark style… easy-to-understand.
  • Author’s Comments – These sections were written by Mike to help you better understand the NEC material, and to bring to your attention things he believes you should be aware of.
  • Full-color detailed graphics to reinforce those difficult concepts and provide instant understanding.

Product Code: 05BK
ISBN: 1-932685-27-8
Pages: 120
Illustrations: 198

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