Trapezoidal Shaped Aluminum Conductor, Steel Supported (ACSS/TW) is a composite conductor made with wires twisted in a concentric-lay pattern. It is built with a central core of steel strands, which has two or more layers of trapezoidal-shaped 1350-O aluminum wires stranded around it. Because the aluminum is fully annealed, or soft, the steel core carries most or all of the mechanical load. The steel core wires are protected from corrosion, and options like a high-strength or an aluminum-clad steel core are available.
It is used for overhead distribution and transmission lines. It is designed to operate continuously at high temperatures (up to 250ยฐC) without losing strength. It also sags less than an ACSR/TW conductor under emergency electrical loads, has excellent self-damping properties, and its final sag is not affected by the long-term creep of aluminum.
The conductor is available in two designs: equal area and equal diameter. The equal area design can carry the same current as a standard ACSS conductor but with a smaller diameter. The equal diameter design can carry more current than a standard ACSS conductor of the same size.
The product is manufactured in compliance with the following international standard:
- ASTM B 857 Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductors, Coated Steel Supported (ACSS/TW).
