Earth Cable Size Chart

For the conductor connecting the main earthing terminal to an earth electrode (e.g., rod, plate):

The size of an earth cable is primarily determined by the size of the . In many residential and commercial standards (such as BS 7671 or the NEC), there are specific ratios you must follow to ensure the ground wire can handle the potential fault current without melting. Earth Cable Size Chart (Standard Metric) earth cable size chart

If you need to calculate the exact size rather than using the table (for example, if the earth cable is a different material than the phase cable, or if fault current is unusually high), use the : For the conductor connecting the main earthing terminal

| Cross-sectional Area of Phase Conductor (L) | Minimum Cross-sectional Area of Protective Conductor (Earth) | | :------------------------------------------: | :----------------------------------------------------------: | | | 1.5 mm² | | 2.5 mm² | 2.5 mm² | | 4 mm² | 4 mm² | | 6 mm² | 6 mm² | | 10 mm² | 10 mm² | | 16 mm² | 16 mm² | | 25 mm² | 16 mm² | | 35 mm² | 16 mm² | | 50 mm² | 25 mm² | | 70 mm² | 35 mm² | | 95 mm² | 50 mm² | | 120 mm² | 70 mm² | | 150 mm² | 95 mm² | | 185 mm² | 95 mm² | | 240 mm² | 120 mm² | earth cable size chart