Switchboard to the Buildings Earth

DANGER

hazard of electric shock, explosion, or arc flash Earthing system is essential for electrical current to flow safely to the ground in the event of a system fault or overload. Effective earthing helps such that the voltage in the system is stable and remains within safe limits. Earthing system ensure the efficient operation of electrical installations and reliable performance of protective relays and control devices. Failure to follow these instructions will result in death or serious injury.

Follow the below steps to install the main earth connection from switchboard to the buildings earth:

1. Slip the connecting bar into the adjacent cubicles supporting structure through the cut out in the cubicle (Figure 29).
2. Screw-fasten connecting bar on both sides to the earth bar, refer to Figure 30.
   NOTE: Comply with the specifications on treatment of contact surfaces and the tightening torques for screw fastenings as per ST0171.

3. Connect earth bus to the earthing system of the switchgear building.

   NOTE: Connecting lines and screw accessories are not included in the scope of supplies.

4. Earthing switch copper braid is connected with cubicle structure and main earth system copper 30 x 8 mm is connected with inter cubicle earth system.

Figure 29
Main Earth Connection from the Switchboard to the Building Earth