In order to achieve the basic "earthing" connection between RM6 and the substation earth, it it not required to have the "additional earth busbar".
As shown below, the position where the substation earthing is applied on the top-back side of the RM6.
The "additional earth busbar" is an option installed in cable compartment which becomes necessary only in case the earth fault current in the RM6 installation is equal to or exceeding 6kA.
The value of earth fault current essentially depends on the electrical network, earthing system/type & estimated fault levels to earth according to limiting impedances.
As shown below, the position where the substation earthing is applied on the top-back side of the RM6.
The "additional earth busbar" is an option installed in cable compartment which becomes necessary only in case the earth fault current in the RM6 installation is equal to or exceeding 6kA.
The value of earth fault current essentially depends on the electrical network, earthing system/type & estimated fault levels to earth according to limiting impedances.
Released for:Schneider Electric South Africa
