Switchboard to the Buildings Earth
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 help ensure the efficient operation of electrical installations and reliable performance of protective relays and control devices.
 DANGER |
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hazard of electric shock, explosion, or arc flash
Ensure to follow the below steps to install the main earth
connection from switchboard to the buildings earth.
Failure to follow these instructions will result in death or serious injury.
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NOTE: During the installation of the end sheets, punch the knock-outs
from the sheets. The earth bars are screw-fastened from cubicle to
cubicle by means of connecting bars.
Follow the below steps to install the main earth connection from switchboard to the buildings earth:
- Slip the connecting bar into the adjacent cubicles supporting structure through the cut out in the cubicle (Figure 32).
- Screw-fasten connecting bar on both sides to the earth bar, refer
to Figure 33.
NOTE: Comply with the specifications on treatment of contact surfaces and the tightening torques for screw fastenings as per ST0171.
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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. - 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 32
Main Earth Connection from the
Switchboard to the Building Earth