[ I_b \leq I_n \leq I_z ] [ I_z = \fracI_nC_a \cdot C_g \cdot C_i \cdot C_c ]

[ A_min = \fracI_sc \cdot \sqrttk ]

If voltage drop exceeds limit, increase cable size. Minimum cross-section for short-circuit:

[ I_0 \geq I_z ] [ \Delta U = \sqrt3 \cdot I_b \cdot L \cdot (R\cos\phi + X\sin\phi) \quad \text(3-phase) ]

[ \Delta U_phase-to-phase \leq \Delta U_max \quad (\texte.g., 3% \text of U_L) ]

Where: (P) = load power (W) (U_L) = line-to-line voltage (V) (\cos\phi) = power factor Choose a standard rating (e.g., 16A, 20A, 32A, 40A) such that:

Electrical Cable Sizing Calculation !link! May 2026

[ I_b \leq I_n \leq I_z ] [ I_z = \fracI_nC_a \cdot C_g \cdot C_i \cdot C_c ]

[ A_min = \fracI_sc \cdot \sqrttk ]

If voltage drop exceeds limit, increase cable size. Minimum cross-section for short-circuit:

[ I_0 \geq I_z ] [ \Delta U = \sqrt3 \cdot I_b \cdot L \cdot (R\cos\phi + X\sin\phi) \quad \text(3-phase) ]

[ \Delta U_phase-to-phase \leq \Delta U_max \quad (\texte.g., 3% \text of U_L) ]

Where: (P) = load power (W) (U_L) = line-to-line voltage (V) (\cos\phi) = power factor Choose a standard rating (e.g., 16A, 20A, 32A, 40A) such that: