IEC 60228

IEC 60228 – Conductors of insulated cables

IEC 60228 is an international standard that specifies the nominal cross-sectional areas of conductors in electric power cables and cords across a wide range, from 0.5 mm² to 3,500 mm². This includes solid, stranded, and Milliken-type conductors made of copper, aluminium, and aluminium alloys. The standard applies to conductors used in both fixed installations and flexible copper conductors.

IEC 60228 also defines the requirements for the number and size of individual wires forming the conductor, as well as the maximum resistance values for each class and size. These characteristics are essential for ensuring electrical performance, mechanical integrity, and compliance with design expectations in low-, medium-, and high-voltage cable systems.

Unless stated otherwise in a particular clause, the standard applies to the conductor as it appears in the finished cable, not to individual conductors prior to inclusion in a cable.

IEC 60228 does not apply to conductors intended for telecommunication purposes. The applicability of IEC 60228 to any specific cable type is determined by the relevant standard covering that cable.

Conductors described in IEC 60228 are expressed using metric sizes, and the document includes informative annexes to support technical understanding and application:

• Annexe B provides temperature correction factors for resistance measurement.
• Annexe C offers guidance on the dimensional limits of circular conductors.