The cable must be rated to carry more current than the breaker. This prevents the cable from melting before the breaker trips. $$I_z \geq I_n$$
Rule: Ib≤InRule: cap I sub b is less than or equal to cap I sub n Step 3: Apply Environmental Correction Factors how to cable size calculation
Using a standard cable sizing table (e.g., IEC 60227), we select a cable with a cross-sectional area of 6 mm². The cable must be rated to carry more