840 – Premises-Powered Broadband Communications Systems
840.2 – Premises-Powered Broadband Communications Systems
Change at a Glance:
Two new definitions were added to 840.2 to define the terms “Broadband” and “Premises-Powered.”
840.2 Definitions. (Premises-Powered Broadband Communications Systems)
The definitions in 805.2, and 820.2 shall apply. The definitions in this section shall apply only within Article 840.
Broadband. Wide bandwidth data transmission that transports multiple signals, protocols, and traffic types over various media types.
Premises-Powered. Using power provided locally from the premises.
840.94 and 840.102 – Premises Circuits Leaving the Building
Change at a Glance:
Two new sections (840.94 and 840.102) were added to Article 840 to provide requirements for premises-powered broadband communication system circuits when they leave the building to power equipment remote to that building.
840.94 Premises Circuits Leaving the Building. (Premises-Powered Broadband Communications Systems)
Where circuits leave the building to power equipment remote to the building or outside the exterior zone of protection defined by a 46 m (150 ft) radius rolling sphere, 805.90 and 805.93 shall apply. Informational Note: See NFPA 780-2017, Standard for the Installation of Lightning Protection Systems, for the application of the term rolling sphere.
840.102 Premises Circuits Leaving the Building. Where circuits leave the building to power equipment remote to the building or outside the exterior zone of protection defined by a 46 m (150 ft) radius rolling sphere, the installation of communications wires and cables shall comply with 800.100 and 800.106, and the installation of coaxial cables shall comply with 820.100 and 800.106.
Informational Note: See NFPA 780-2017, Standard for the Installation of Lightning Protection Systems, for the application of the term rolling sphere.
840.160 – Premises-Powered Broadband Communication Systems
Change at a Glance:
Revised text identifies listing provisions for communications cables, powered communications equipment, and the power source.
840.160 Powering Circuits. (Premises-Powered Broadband Communication Systems)
Communications cables listed in accordance with 805.179, in addition to carrying the communications circuit, shall also be permitted to carry circuits for powering communications equipment listed in accordance with 805.170. The power source shall be listed in accordance with 840.170(G). Installation of the listed 4-pair communications cables for a communications circuit or installation where 4-pair Where the power supplied over a communications cable to communications equipment is greater than 60 watts, communication cables and the power circuit shall comply with 725.144 where communications cables are substituted used in place of for Class 2 and Class 3 cables in accordance with 725.154(A) shall comply with 725.144.
Exception: Installing communications cables in compliance with 725.144 shall not be required for listed 4-pair communications cables where the rated current of the power source does not exceed 0.3 amperes in any conductor 24 AWG or larger.
Informational Note: A typical communications cable for this application is a 4-pair cable sometimes referred to as Category 5e (or higher) LAN cable or balanced twisted pair cable. These types of cables are often used to provide Ethernet- and Power over Ethernet (PoE)–type services. A large number of such powering cables bundled together can cause overheating of the wiring if not controlled as described in Table 725.144.