COMMUNICATIONS CIRCUITS

A. General 800-1. Scope. This article covers telephone, telegraph (except radio), outside wiring for fire alarm and burglar alarm, and similar central station systems; and telephone systems not connected to a central station system but using similar types of equipment, methods of installation, and maintenance. (FPN No. 1): For further information for fire alarm, guard tour, sprinkler waterflow, and sprinkler supervisory systems, see Article 760. (FPN No. 2): For installation requirements of optical fiber cables, see Article 770. 800-2. Definitions. See Article 100. For purposes of this article, the following additional definitions apply: Cable: A cable is a factory assembly of two or more conductors having an overall covering. Cable Sheath: A sheath is a covering over the conductor assembly that may include one or more metallic members, strength members, or jackets. Point of Entrance: The point of entrance within a building is the point at which the wire or cable emerges from an external wall, from a concrete floor slab, or from a rigid metal conduit or an intermediate metal conduit grounded to an electrode in accordance with Section 800-40(b). Wire: A wire is a factory assembly of one or more insulated conductors without an overall covering. 800-3. Hybrid Power and Communications Cables. The provisions of Section 780-6 shall apply for listed hybrid power and communications cables in closed-loop and programmed power distribution. (FPN): See Section 800-51(i) for hybrid power and communications cable in other applications. 800-4. Equipment. Equipment intended to be electrically connected to a telecommunications network shall be listed for the purpose. (FPN): One way. to determine applicable requirements is to refer to the Standard for Telephone Equipment, UL 1459-1987, or Communication Circuit Accessories, UL 1863-1990. Exception No. 1: For other than wires, cables, grounding conductors, and protectors, this listing requirement shall not apply to premises wiring components, such as plugs, jacks, connectors, terminal blocks, and crossconnect assemblies that were manufactured before October 1, 1990 and all other equipment manufactured before July 1, 1991. 70-792 NATIONAL ELECTRICAL CODE Exception No. 2: This listing requirement shall not apply to test equipment intended for temporary connection to a telecommunications network by qualified persons during the course of installation, maintenance, or repair of telecommunications equipment or systems. 800-5. Access to Electrical Equipment Behind Panels Designed to Allow Access. Access to equipment shall not be denied by an accumulation of wires and cables that prevents removal of panels, including suspended ceiling panels. 800-6. Mechanical Execution of Work. Communication circuits and equipment shall be installed in a neat and workmanlike manner. B. Conductors Outside and Entering Buildings 800-10. Overhead Communications Wires and Cables. Overhead communications wires and cables entering buildings shall comply with (a) and (b) below. (a) On Poles and In-Span. Where communications wires and cables and electric light or power conductors are supported by the same pole or run in parallel in-span, the following conditions shall be met: (1) Relative Location. Where practicable, the communications wires and cables shall be located below the electric light or power conductors. (2) Attachment to Crossarms. Communications wires and cables shall not be attached to a crossarm that carries electric light or power conductors. (3) Climbing Space. The climbing space through communications wires and cables shall comply with the requirements of Section 225-14(d). (4) Clearance. Supply service drops of 0-750 volts running above and parallel to communications service drops shall be permitted to have a minimum separation of 12 inches (30.48 cm) at any point in the span, including the point of and at their attachment to the building, provided the nongrounded conductors are insulated and that a clearance of 40 inches (1.02 m) is maintained between the two services at the pole. (b) Above Roofs. Communications wires and cables shall have a vertical clearance of not less than 8 feet (2.44 m) from all points of roofs above which they pass. Exception No. 1: Auxiliary buildings, such as garages and the like. Exception No. 2: A reduction in clearance above only the overhanging portion of the roof to not less than 18 inches (457 mm) shall be permitted if (1) not more than 4 feet (1.22 mm) of communications service-drop conductors pass above the roof overhang and (2) they are terminated at a through- or above-the-roof raceway or approved support. Exception No. 3: Where the roof has a slope not less than 4 inches (102 mm) in 12 inches (305 mm), a reduction in clearance to not less than 3 feet (914 mm) shall be permitted. ARTICLE 800 - COMMUNICATIONS CIRCUITS 70-793 800-11. Underground Circuits Entering Buildings. Underground communications wires and cables entering buildings shall comply with (a) and (b) below. (a) With Electric Light or Power Conductors. Underground communications wires and cables in a raceway, handhole, or manhole containing electric light or power conductors shall be in a section separated from such conductors by means of brick, concrete, or tile partitions. (b) Underground Block Distribution. Where the entire street circuit is run underground and the circuit within the block is so placed as to be free from likelihood of accidental contact with electric light or power circuits of over 300 volts to ground, the insulation requirements of Sections 800-12(a) and 800-12(c) shall not apply, insulating supports shall not be required for the conductors, and bushings shall not be required where the conductors enter the building. 800-12. Circuits Requiring Primary Protectors. Circuits that require primary protectors as provided in Section 800-30 shall comply with the following: (a) Insulation, Wires, and Cables. Communications wires and cables without a metallic shield, running from the last outdoor support to the primary protector, shall be listed as being suitable for the purpose and having current-carrying capacity as specified in Section 800-30(a)(1)(b) or 800-30(a)(1)(c). (b) On Buildings. Communications wires and cables in accordance with Section 800-12(a) shall be separated at least 4 inches (102 mm) from electric light or power conductors not in a raceway or cable, or be permanently separated from conductors of the other system by a continuous and firmly fixed nonconductor in addition to the insulation on the wires, such as porcelain tubes or flexible tubing. Communications wires and cables in accordance with Section 800-12(a) exposed to accidental contact with electric light and power conductors operating at over 300 volts to ground and attached to buildings shall be separated from woodwork by being supported on glass, porcelain, or other insulating material. Exception: Separation from woodwork shall not be required where fuses are omitted as provided for in Section 800-31(a), or where conductors are used to extend circuits to a building from a cable having a grounded metal sheath. (c) Entering Buildings. Where a primary protector is installed inside the building, the communications wires and cables shall enter the building either through a noncombustible, nonabsorbent insulating bushing, or through a metal raceway. The insulating bushing shall not be required where the entering communications wires and cables (1) are in metalsheathed cable; (2) pass through masonry; (3) meet the requirements of Section 800-12(a) and fuses are omitted as provided in Section 800-31(a); or (4) meet the requirements of Section 800-12(a) above and are used to extend circuits to a building from a cable having a grounded metallic sheath. Raceways or bushings shall slope upward from the outside or, where this cannot be done, drip loops shall be formed in the communications wires and cables immediately before they enter the building. 70-794 NATIONAL ELECTRICAL CODE Raceways shall be equipped with an approved service head. More than one communications wire and cable shall be permitted to enter through a single raceway or bushing. Conduits or other metal raceways located ahead of the primary protector shall be grounded. 800-13. Lightning Conductors. Where practicable, a separation of at least 6 feet (1.83 m) shall be maintained between open conductors of communications systems on buildings and lightning conductors. C. Protection 800-30. Protective Devices. (a) Application. A listed primary protector shall be provided on each circuit run partly or entirely in aerial wire or aerial cable not confined within a block. Also, a listed primary protector shall be provided on each circuit, aerial or underground, so located within the block containing the building served as to be exposed to accidental contact with electric light or power conductors operating at over 300 volts to ground. In addition, where there exists a lightning exposure, each interbuilding circuit on a premises shall be protected by a listed primary protector at each end of the interbuilding circuit. Installation of primary protectors shall also comply with