Bs7671 Cable Sizing Direct

[ V_d = \frac(mV/A/m) \times I_b \times L1000 \quad \text(in volts) ]

[ I_z = I_t \times C_a \times C_g \times C_d \times C_i \times C_c ] bs7671 cable sizing

Where ( L ) is the cable length in metres (line + neutral – so for single-phase, use the tabulated mV/A/m directly; for three-phase, note correction). [ V_d = \frac(mV/A/m) \times I_b \times L1000

[ Z_s = Z_DB + (R_1 + R_2) \times L ]