[ k \times S \ge I_sc \times \sqrtt ]
This should be ≤ allowable limit (typically 3–5%). For a fault lasting ( t ) seconds, the cable must withstand: cable size calculations
Example standard ratings: 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A, etc. [ I_min = \fracI_nC_t \times C_g \times C_i \times C_s \times C_r ] [ k \times S \ge I_sc \times \sqrtt
[ I_b = \fracP\sqrt3 \times V_L \times \cos\phi ] cable size calculations