This specification covers the standard requirements for bare combination unilay-stranded conductors made from round wires of aluminum 1350 and 8000 series of aluminum alloys, for insulated conductors to be used for electrical purposes. Aluminum 1350 wires in tempers -H19, -H16 or -H26, -H14 or -H24, and -H142 or -H242 and 8000 series aluminum alloy wires in tempers 0 and H1X or H2X are permitted. These conductors shall be constructed with a central core wire surrounded by two layers of helically laid wires, resulting in an outer diameter equal to the compressed-stranded equivalent conductors. Electric-butt welds, cold pressure welds, or electric-butt cold-upset welds may be made in the finished individual wires composing the conductor. Mechanical (tension) and electrical tests shall be performed on the wires composing the conductors that are annealed and not annealed after stranding. The mass and electrical resistance of a unit length of stranded conductor shall be determined as a function of the length of lay. The conductors shall meet the breaking strength, tensile strength, and bending strength requirements.

1.1 This specification covers bare combination unilay-stranded conductors made from round wires of aluminum 1350 and 8000 series of aluminum alloys, for insulated conductors for electrical purposes. Aluminum 1350 wires in tempers -H19 (extra hard), -H16 or -H26 (¾ hard), -H14 or -H24 (½ hard), and -H142 or -H242 (½ hard) and 8000 series aluminum alloys wires in tempers “0” and H1X or H2X are permitted. These conductors shall be constructed with a central core wire surrounded by two layers of helically laid wires, resulting in an outer diameter equal to the compressed-stranded equivalent conductors.

Note 1—For the purpose of this specification, combination unilay conductor is defined as follows: a central core wire surrounded by a layer of six helically laid wires of the same diameter as the core wire with a helically laid outer layer containing six smaller wires alternated between six wires of the same diameter as the wires in the layer underneath. Both layers have a common length and direction of lay (see Fig. 1).

1.1.1 For the purpose of this specification, normal conductor classification (Class AA, A, B, C) is not applicable, as these conductors are intended for subsequent insulation. The descriptive term combination unilay-stranded shall be used in place of conductor classification (Note 2 and Note 3).

Note 2—Prior to 1975, aluminum 1350 was designated as EC aluminum.

Note 3—The aluminum and temper designations conform to ANSI Standard H35.1. Aluminum 1350 corresponds to Unified Numbering System A91350 in accordance with Practice E 527. Unified Numbering System alloy designations for 8000 Series aluminum alloys in accordance with Practice E 527 are listed in Table number 1 of Specification B 800.

1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

FIG. 1 Cross Section of Conductor