In one of LV Panels, The mains rating is 100A 4P+E 415VAC.
The phase cables are 1Cx25Sqmm Low smoke Fire Retardant 1.1kV Cables
The Earth cable is 1Cx16Sqmm Low smoke Fire retardant PVC insulated 1.1kV Cables
The earth cable enters at the bottom to the Earth Busbar which is 60x3mm Tinned Cu.
The earthing cable is distributed in the busbar for many electrical components.
The Panel door is 2mm Thick and it is powder coated for 80Microns.
All switchgear components are mounted in the Mounting panel inside the enclosure which is equipotentially bonded
Question - What should be the cable size for Panel Door earthing to the Earth busbar.
In general, many panel manufacture consider 2.5Sqmm cable for Door earthing as standard.
I have not seen any standard for sizing the door Earthing.
What is the logic behind such selection?
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