scope:

1.1 This specification covers shaped wire compact concentric-lay-stranded aluminum conductors, steel supported (ACSS/TW) for use as overhead electrical conductors (see Explanatory Note 1).

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.2.1 Exceptions-For conductor sizes designated by AWG or kcmil sizes, the requirements in SI units are numerically converted from the corresponding requirements in inch-pound units. For conductor sizes designated by SI units only, the requirements are stated or derived in SI units. For density, resistivity, and temperature, the values stated in SI units are to be regarded as standard.

1.3 ACSS/TW is designed to increase the aluminum area for a given diameter of conductor by the use of trapezoidal shaped wires (TW), or to reduce the diameter for a given area of aluminum. The conductors consist of a central core of round steel wire(s) surrounded by two or more layers of trapezoidal aluminum 1350-0 wires. Different strandings of the same size of conductor are identified by type, which is the approximate ratio of steel area to aluminum area expressed in percent (see Table 1, Table 2, and Table 3). For the purpose of this specification, the sizes listed in Table 1 and Table 2 are tabulated on the basis of the finished conductor having an area or outside diameter equal to that of specified sizes of standard ACSR, ACSS, and ACSR/TW so as to facilitate conductor selection.

TABLE 1 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, Coated Steel Supported^ANote 1-Sized to have area equal aluminum cross-sectional area to an ACSR or ACSS, Class AA conductor.

^A Conversion factors:
   1 cmil = 5.067E−04 mm ² (0.0005067 mm³)
   1 in. = 2.54E+01 mm (25.4 mm)
   1 lb/1000ft = 1.488 kg/km
   1 ft = 3.048E−01 m (0.3048 m)
   1 lb = 4.536E−01 kg (0.4536 kg)
   1 lbf = 4.448E−03 kN (0.0044448 kN)^B Code Words shown in this column are obtained from "Publication 50, Code Words for Overhead Aluminum Electrical Conductors," by the Aluminum Association. They are provided for information only.^C See Explanatory Note 4.TABLE 2 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, Coated Steel Supported^ANote 1-Sized to have a diameter equal to a concentric round ACSR or ACSS, Class AA conductor.

^A Conversion factors:
   1 cmil = 5.067E−04 mm ² (0.0005067 mm²)
   1 in. = 2.54E+01 mm (25.4 mm)
   1 lb/1000 ft = 1.488 kg/km
   1 ft = 3.048E−01 m (0.3048 m)
   1 lb = 4.536E−01 kg (0.4536 kg)
   1 lbf = 4.448E−03 kN (0.004448 kN)^B Code Words shown in this column are obtained from "Publication 50, Code Words for Overhead Aluminum Electrical Conductors," by the Aluminum Association. They are provided for information only.^C See Explanatory Note 4.TABLE 3 Comparison of ACSS/TW With Equivalent Stranding of ACSR^A and ACSS^B

^A The equivalent stranding is that stranding of conventional ACSR that has the same area of aluminum and steel as a given ACSS/TW type.^B The equivalent stranding is that stranding of conventional ACSS that has the same area of aluminum and steel as a given ACSS/TW type.^C ACSS/TW type number is the approximate ratio of the steel area to the aluminum area in percent.^D See Specifications B549 and B856.

abstract: