Practical method for determining the smallest allowable cross-sectional area of circuit conductors
From Electrical Installation Guide
The reference international standard for the study of cabling is IEC 60364-5-52: “Electrical installation of buildings - Part 5-52: Selection and erection of electrical equipment - Wiring system”.
A summary of this standard is presented here, with examples of the most commonly used methods of installation. The current-carrying capacities of conductors in all different situations are given in annex A of the standard. A simplified method for use of the tables of annex A is proposed in informative annex B of the standard.