Chapter 14 - Lighting

14.6. Power Service

14.6.1. Grounding System

The ground rods shall be copper clad steel, minimum ¾-in diameter, 10-ft. long.  The buried ground conductors shall be stranded copper.  All the underground connections in the grounding system shall be made using exothermic weld (cadweld) process.

A ground rod shall be provided at each conventional light pole and connected in the pole base using a ground conductor.  A ground grid consisting of four ground rods at the corners of the high mast lighting foundation shall be provided.  The rods shall be connected to each other using #2 AWG stranded copper conductor to form a square ground grid.  A #2 AWG bare stranded copper conductor shall be cadwelded to the grid and brought into the tower base to connect to the pole.

A ground grid consisting of three ground rods located at the apexes of a 10-ft. equilateral triangle and connected to each other using #2 AWG stranded copper conductors shall be provided at each power service.  An adequately sized stranded copper conductor shall be connected to the ground grid and routed to main service disconnecting means. Appropriately sized insulated ground conductor(s) shall be provided in the conduits with the branch circuits.