I am reviewing the NEC to determine if fiber optic cable can be in the same junction box / pull box as power wire. The fiber optic will be nonconductive, the power wire will be under 600V, and the systems are not related.
Based on 2008 NEC article 770.133.A, it says the fiber can occupy the same cable tray or raceway as power. It does not include junction / pull boxes. Additionally, I would not consider a junction / pull box to be considered a raceway based on the definition of a raceway.
Further down it says nonconductive can't be in enclosures etc with electrical splices but it doesin't say anything about if there are no splices so does this mean it can?
Additionally, there is exception #1. Exception #1 says the fiber can be in the same enclosure with the power if the same function. Does this exception apply to all of 770.133.A meaning fiber can only be in the same JB as power if the systems are related or does the exception only apply to the last paragraph where it discusses fiber in the same enclosure as spliced power?
770.133 Installation of Optical Fibers and Electrical Conductors.
See related ROP (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 in factory- 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 1, nonpower-limited fire alarm, and medium-power network-powered broadband communications circuits are separated from all of the optical fiber cables by a permanent barrier or listed divider.
