Optical fiber cables entering the building or terminating on the outside of the building shall comply with 770.93(A) or (B).
(A) Entering Buildings. In installations where an optical fiber cable is exposed to contact with electric light or power conductors and the cable enters the building, the non-current-carrying metallic members shall be either grounded as specified in 770.100, or interrupted by an insulating joint or equivalent device. The grounding or interruption shall be as close as practicable to the point of entrance.
(B) Terminating On the Outside of Buildings. In instal- lations where an optical fiber cable is exposed to contact with electric light or power conductors and the cable is terminated on the outside of the building, the non-current-carrying metallic members shall be either grounded as specified in 770.100, or interrupted by an insulating joint or equivalent device. The grounding or interruption shall be as close as practicable to the point of termination of the cable.
IV. Grounding Methods
770.100 Entrance Cable Grounding. Where grounded, the non-current-carrying metallic members of optical fiber cables entering buildings shall be grounded as specified in 770.100(A) through (D).
(A) Grounding Conductor.
(1) Insulation. The grounding conductor shall be insulated and shall be listed.
(2) Material. The grounding conductor shall be copper or other corrosion-resistant conductive material, stranded or solid.
(3) Size. The grounding conductor shall not be smaller than 14 AWG. It shall have a current-carrying capacity approximately equal to or greater than that of the metallic member(s). The grounding conductor shall not be required to exceed 6 AWG.
(4) Run in Straight Line. The grounding conductor shall be run to the grounding electrode in as straight a line as practicable.
(5) Physical Damage. Where necessary, the grounding conductor shall be guarded from physical damage. Where the grounding conductor is run in a metal raceway, both ends of the raceway shall be bonded to the grounding conductor or the same terminal or electrode to which the grounding conductor is connected.
(B) Electrode. The grounding conductor shall be con- nected in accordance with 770.100(B)(1), (B)(2), or (B)(3).
(1) In Buildings or Structures with an Intersystem Bonding Termination. If the building or structure served has an intersystem bonding termination, the grounding conductor shall be connected to the intersystem bonding termination.
(2) In Buildings or Structures with Grounding Means.
If the building or structure served has no intersystem
bonding termination, the grounding conductor shall be
connected to the nearest accessible location on the
following:
(1) The building or structure grounding electrode system as covered in 250.50
(2) The grounded interior metal water piping system, within 1.5 m (5 ft) from its point of entrance to the building, as covered in 250.52
(3) The power service accessible means external to enclosures as covered in 250.94
(4) The metallic power service raceway
(5) The service equipment enclosure
(6) The grounding electrode conductor or the grounding electrode conductor metal enclosure
(7) The grounding conductor or the grounding electrode of a building or structure disconnecting means that is grounded to an electrode as covered in 250.32