Earthing at telecom exchange, data centre, IT console, network control room

Bonding of lightning down conductor and earth electrode

Ref:  NEC 250.106 and NFPA 780 section 4.14.

·         The electrical system and communications grounding electrodes, along with all incoming or exiting metallic piping in the earth must be bonded to the lightning-protection grounding electrode system.

·         Connections between the down conductors of lightning arrester and grounding electrodes may be made by bolting, brazing, and welding or high compression connector.

earthing at telecom, data center, computer network

·         Clamps suitable may also be used.

·         Where more than one utility exists at a building or structure, they shall be effectively bonded together to form a common grounding electrode system and the MGB (main grounding bus bar).  For example: a metallic underground water pipe, the metal frame of the building or structure, concrete-encased electrode, a ground ring conductor encircling the building or structure, rod or pipe electrodes and lightning electrodes etc. (Ref: NFPA 70-2005).

Resistance value: equal or less than 5 ohm