Cable Sizing Explained: Voltage Drop, Ampacity and Short Circuit

What the video shows

The five IEC 60364 checks for sizing a cable, with a worked example of a 22 kW motor 80 m from the panel, in 6:07: current-carrying capacity (the same 16 mm² copper PVC cable carries 52–62 A in conduit, 76 A clipped direct and 80 A on a perforated tray; 57 A with 0.87 at 40 °C and 0.82 for three circuits), overload protection (I_B ≤ I_n ≤ I_z), voltage drop (3 % lighting, 5 % other loads; also during motor starting), short-circuit withstand (k²S² ≥ I²t; at least 14.8 mm² copper XLPE for 15 kA cleared in 20 ms) and the earth fault loop (with a type C 50 A breaker the maximum length is 48 m on 6 mm² and 81 m on 10 mm²). Harmonics in the neutral, and the result: current alone says 6 mm², but the breaker and the fault loop need 10 mm².