Connector Products And Accessories for Electrical Earthing or Grounding System shall be as follows:
A. Copper or copper alloy, purpose made, of approved design, compatible with points of connection, and of adequate cross-section and current carrying capacity.
B. Connections to metallic structures for earthing conductors and bonding conductors between electrically separate parts of a structure shall be either by direct exothermic welding or by bolting using a stud welded to the structure. Drilling of a structural member for a directly bolted connection shall only be carried out to the approval of the Engineer.
- Bolted Connectors and Clamps: Bolted-pressure-type connectors and clamps, or compression type. Bolts, nuts and washers are to be high quality phosphor bronze or copper silicon alloys. Bolted connections are not permitted in run of the earthing conductors unless approved by the Engineer.
- Welded Connectors: Exothermic-welded type, in kit forms, and selected per manufacturer's written instructions. Welded connectors are to be used only in inaccessible locations and at "T" joints, to the approval of the Engineer.
C. Bi-metallic connectors shall be used between conductors of dissimilar materials and insulating material shall be interposed between metallic fittings and structures of dissimilar materials to prevent corrosion.
D. When the reinforcing in concrete is used as a part of the earthing system the fittings used to provide a connection point at the surface of the concrete shall be exothermically welded to a reinforcing bar. This fitting shall be provided with a bolted connection for an earthing conductor. The main bars in the reinforcing shall be welded together at intervals to ensure electrical continuity throughout the reinforcing.
E. No connections shall be made to reinforcing bars and other steelwork, which do not form part of the earthing system and are completely encased in concrete.