[ I_f = \fracU_0Z_s ]
[ S = \frac\sqrtI^2 \times tk ]
The adiabatic minimum is only 1 mm². However, the simplified table (BS 7671) requires: line conductor = 6 mm² (for 32 A), earth conductor ≥ 6 mm² (since line ≤ 16 mm²). Therefore, select —governed by the table, not the adiabatic equation. earth cable size calculation