This specification covers bare rope-lay-stranded conductors having bunch-stranded members from round copper wires, either uncoated or coated with tin, lead, or lead-alloy for use in electrical conductors. Rope-lay-stranded conductors having bunch-stranded members are classified as Class I, Class K, and Class M. Necessary joints in wires or in groups of wires shall be made in accordance with accepted commercial practice, taking into account the size of the wire or group of wires as related to the size of the entire conductor. Conductors of the same size and description furnished on one order shall have the same lay. In very flexible conductors, such as welding conductor, the direction of lay of the stranded members forming rope-lay-stranded conductor may be in the same, rather than in teversed. For the purpose of calculating the mass, cross sections, etc., the density of copper shall be taken. The mass and electrical resistance of a unit length of stranded conductor as a function of the length of lay shall be measured.

1.1 This specification covers bare rope-lay-stranded conductors having bunch-stranded members made from round copper wires, either uncoated or coated with tin, lead, or lead-alloy for use as electrical conductors (Explanatory Notes 1 and 2).

1.2 Coated wires shall include only those wires with finished diameters and densities substantially equal to the respective diameters and densities of uncoated wires.

1.3 The values stated in inch-pound or SI units are to be regarded separately as standard. Each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification. For conductor sizes designated by AWG or kcmil, the requirements in SI units have been numerically converted from corresponding values, stated or derived, in inch-pound units. For conductor sizes designated by SI units only, the requirements are stated or derived in SI units.

1.3.1 For density, resistivity, and temperature, the values stated in SI units are to be regarded as standard.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.