ASTM B778 : 02(2012)

Standard Specification for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors (AAC/TW)

Standard Details

1.1 This specification covers shaped wire compact concentric-lay-stranded aluminum conductor (AAC/TW) and its component wires for use as overhead electrical conductors (Explanatory Note 1 and Note 2).

1.2 The values stated in inch-pound units are to be regarded as the standard with the exception of temperature and resistivity. The SI equivalents of inch-pound units may be approximate.

Note 1—AAC/TW is designed to increase the aluminum area for a given diameter of conductor by the use of trapezoidally shaped wires (TW). The conductors consist of a central core of one round aluminum wire or a seven-strand compact round core surrounded by two or more layers of trapezoidal aluminum 1350-H19 wires. For the purposes of this specification, the sizes listed are tabulated on the basis of the finished conductor having an area equal to that of specific sizes of standard AAC (Table 1) or in fixed diameter increments (Table 2) so as to facilitate conductor selection.

TABLE 1 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors Sized to Have Areas Equal to AAC Size

Code Word^A	AAC/TW Conductor size		Nominal Outside Diameter		Number of Aluminum Wires	Number of Layers	Nominal Mass		Rated Strength
Code Word^A	kcmil	mm	in.	mm	Number of Aluminum Wires	Number of Layers	lb/1000ft	kg/km	1000 lbf	kN
Tulip/TW	336.4	170	0.612	15.5	17	2	315.3	469.4	6.02	26.8
Canna/TW	397.5	201	0.661	16.8	17	2	372.6	554.7	6.96	31
Cosmos/TW	477.0	242	0.720	18.3	17	2	447.1	665.6	8.36	37.2
Zinnia/TW	500.0	253	0.736	18.7	17	2	468.7	697.7	8.76	39
Mistletoe/TW	556.5	282	0.775	19.7	17	2	521.6	776.5	9.75	43.4
Meadowsweet/TW	600.0	304	0.803	20.4	17	2	562.4	837.2	10.52	46.8
Orchid/TW	636.0	322	0.825	21.0	17	2	596.1	887.4	11.1	49.4
Verbena/TW	700.0	355	0.864	21.9	17	2	656.1	976.7	12.3	54.7
Nasturtium/TW	750.0	380	0.893	22.7	17	2	702.1	1045	13.1	58.3
Arbutus/TW	795.0	403	0.919	23.3	17	2	745.1	1109	13.6	60.5
Cockscomb/TW	900.0	456	0.990	25.1	31	3	843.6	1256	15.4	68.5
Magnolia/TW	954.0	483	1.018	25.9	31	3	894.2	1331	16.4	72.9
Hawkweed/TW	1000.0	507	1.041	26.4	31	3	937.3	1395	17.1	76.1
Bluebell/TW	1033.5	524	1.057	26.8	31	3	968.7	1442	17.7	78.7
Marigold/TW	1113.0	564	1.095	27.8	31	3	1043.2	1553	19.1	85.0
Hawthorn/TW	1192.5	604	1.132	28.8	31	3	1117.7	1664	20.4	90.7
Narcissus/TW	1272.0	644	1.168	29.7	31	3	1192.2	1775	21.8	97.0
Columbine/TW	1351.5	685	1.202	30.5	31	3	1266.3	1885	23.2	103
Carnation/TW	1431.0	725	1.236	31.4	31	3	1341.3	1997	24.0	107
Coreopsis/TW	1590.0	805	1.315	33.4	49	4	1490.3	2219	27.0	120
Jessamine/TW	1750.0	887	1.377	35.0	49	4	1640.3	2442	29.7	132
Cowslip/TW	2000.0	1013	1.468	37.3	49	4	1893.0	2818	33.9	151
Lupine/TW	2500.0	1266	1.648	41.9	71	5	2366.2	3522	41.9	186
Trillium/TW	3000.0	1520	1.799	45.7	71	5	2839.5	4227	50.3	224

^A 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.

TABLE 2 Construction Requirements for Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, in Fixed-Diameter Increments

Code Word^A

AAC/TW
Conductor Size

Nominal Outside
Diameter

Number of
Aluminum
Wires

Number
of Layers

Nominal Mass

Rated Strength

kcmil

in.

lb/1000 ft

kg/km