770-Optical Fiber Cables and Raceways: Page 5 of 9

You are here

optical fiber cables are installed in raceway without current-carrying conductors, the raceway fill tables of Chapter 3 and Chapter 9 shall not apply. Where nonconductive optical fiber cables are installed with electric conductors in a raceway, the raceway fill tables of Chapter 3 and Chapter 9 shall apply.

770.113 Installation of Optical Fiber Cables. Optical fi- ber cables installed in buildings shall be listed.

Exception: Optical fiber cables that comply with 770.48 shall not be required to be listed.

770.133 Installation of Optical Fibers and Electrical
Conductors.
(A) With Conductors for Electric Light, Power, Class 1, Non-Power-Limited Fire Alarm, or Medium Power Network-Powered Broadband Communications Circuits. When optical fibers are within the same composite cable for electric light, power, Class 1, non-power- limited fire alarm, or medium-power network-powered broadband communications circuits operating at 600 volts or less, they shall be permitted to be installed only where the functions of the optical fibers and the electrical conductors are associated.
Nonconductive optical fiber cables shall be permitted to occupy the same cable tray or raceway with conductors for electric light, power, Class 1, non-power- limited fire alarm, Type ITC, or medium-power network- powered broadband communications circuits, operating at 600 volts or less. Conductive optical fiber cables shall not be permitted to occupy the same cable tray or raceway with conductors for electric light, power, Class
1, non-power-limited fire alarm, Type ITC, or medium-
power network-powered broadband communications
circuits.
Optical fibers in composite optical fiber cables containing only current-carrying conductors for electric light, power, Class 1 circuits rated 600 volts or less shall be permitted to occupy the same cabinet, cable tray, outlet box, panel, raceway, or other termination enclosure with conductors for electric light, power, or Class 1 circuits operating at 600 volts or less.
Nonconductive optical fiber cables shall not be permitted to occupy the same cabinet, outlet box, panel, or similar enclosure housing the electrical terminations of an electric light, power, Class 1, non-power-limited fire alarm, or medium-power network-powered broadband communications circuit.

Exception No. 1: Occupancy of the same cabinet, outlet box, panel, or similar enclosure shall be permitted where nonconductive optical fiber cable is functionally associated with the electric light, power, Class 1, non- power-limited fire alarm, or medium-power network- powered broadband communications circuit.

Exception No. 2: Occupancy of the same cabinet, outlet box, panel, or similar enclosure shall be permitted where nonconductive optical fiber cables are installed infactory-or field-assembled control centers.

Exception No. 3: In industrial establishments only, where conditions of maintenance and supervision

ensure that only qualified persons service the installation, nonconductive optical fiber cables shall be permitted with circuits exceeding 600 volts.

Exception No. 4: In industrial establishments only, where conditions of maintenance and supervision ensure that only qualified persons service the installation, optical fibers in composite optical fiber cables containing current-carrying conductors operating over 600 volts shall be permitted to be installed.

Exception No. 5: Where all of the conductors of electric light, power, Class I, nonpower-limited fire alarm, and medium-power network-powered broadband communications circuits are separated from all of the optical fiber cables by a permanent