[upd]: Cable Calc Formula

The second constraint is voltage drop, often the limiting factor for long runs.

The nameplate current of a cable is reduced by: cable calc formula

In non-linear loads, harmonic currents cause extra (I^2R) losses. The effective RMS current is: The second constraint is voltage drop, often the

(IEC 60364-5-52): Base cable 120 mm² Cu XLPE → 380 A in free air. Derate: (k_amb = 0.87), (k_group = 0.8) → (380 \times 0.87 \times 0.8 = 264 A) → too low. Try 185 mm² → base 500 A → derated = (500 \times 0.696 = 348 A) — acceptable. Derate: (k_amb = 0

[ R_ac = R_dc \left(1 + y_s + y_p\right) ] Where (y_s) (skin) and (y_p) (proximity) depend on frequency and conductor spacing.

[ I = \sqrt\frac\theta_max - \theta_ambR_dc \cdot \left(1 + \alpha(\theta_max - 20)\right) \cdot \left( R_th \right) ]

Using the Cable Calc formula: