How To Cable Size Calculation [upd] Review

Choose the next larger cable size if the derated value is insufficient. Long circuits may require a larger cable to keep voltage drop within limits.

[ V_d = \frac2 \times L \times I \times (R\cos\phi + X\sin\phi)1000 ] Where R and X are resistance and reactance (ohms/km) from cable data. how to cable size calculation