IEC 60228

IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables.

Among other things, it defines a set of standard wire cross-sectional areas:

International standard wire sizes (IEC 60228)
0.5 mm2 0.75 mm2 1 mm2 1.5 mm2 2.5 mm2 4 mm2
6 mm2 10 mm2 16 mm2 25 mm2 35 mm2 50 mm2
70 mm2 95 mm2 120 mm2 150 mm2 185 mm2 240 mm2
300 mm2 400 mm2 500 mm2 630 mm2 800 mm2 1000 mm2

In engineering applications, it is often most convenient to describe a wire in terms of its cross-section area, rather than its diameter, because the cross section is directly proportional to its strength and weight, and inversely proportional to its resistance. The cross-sectional area is also related to the maximum current that a wire can carry safely.

This document is one considered Fundamental in that it does not contain reference to any other standard.

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