Aluminum Conductor Steel supported (ACSS)

Aluminum Conductor Steel supported (ACSS)

Applications

Aluminum Conductor, Steel Supported (ACSS) are used for overhead distribution and transmission lines. They are especially useful in reconductoring applications requiring increased current with existing tensions and clearances; new line applications where structures can be economized due to reduced sag; new line applications requiring high emergency loadings; lines where Aeolian vibration is a problem.

Features and advantages

ACSS conductors are similar to conventional ACSR with some very important additional advantages. ACSS can operate continuously at high temperatures (200°C) without damage; it sags less under emergency electrical loadings than ACSR; and its final sags are not affected by long time creep of the aluminum.

Hi Temp conductors provide distinct advantages for certain transmission line applications:

• Operates continuously at high temperatures up to 200ºC with appropriate steel core coating vs. 100ºC for standard ACSR

• Carries substantially more current than standard ACSR

• Less susceptible to aeolian vibration fatigue due to the very low mechanical load on the annealed aluminum wire

• Can be installed to the maximum tensions allowed by NESC

• Minimum average conductivity of 63% IACS exceeds average conductivity of 61.2% for EC 1350 H19 aluminum

• Reduced sag allows for lower transmission tower height

• Long term creep is not a factor

Structure

ACSS is a composite concentric-lay-stranded cable. The steel strands form the central core of the cable around which is stranded one or more layers of aluminum 1350-0 wires. The “O” temper of the aluminum, a fully annealed or soft temper, causes most or all of the mechanical load on ACSS to be carried by the steel. The steel core may consist of 7, 19, 37 or more wires. They are protected from corrosion by galvanizing or aluminizing. Class A zinc coating is usually adequate for ordinary environments. For greater protection Class B and C galvanized or aluminized coatings may be specified. A special high strength steel core with Class A galvanizing is also available. Type MA, Mischmetal, coated steel core is also available.

Specification

Sim Noor Yazdan,s ACSS conductor meets or exceeds the following ASTM specifications:

• B341 Aluminum-Coated Steel Core Wire for Aluminum Conductors, Steel Reinforced.

• B500 Metallic Coated Stranded Steel Core For Aluminum Conductors, Steel Reinforced.

• B609 Aluminum 1350 Round Wire, Annealed and Intermediate Tempers, for electrical purposes.

• B802 Zinc-5% Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Aluminum Conductors, Steel Reinforced.

• B803 High-Strength Zinc-5% Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Aluminum and Aluminum-Alloy Conductors, Steel Reinforced.

• B856 Concentric-Lay-Stranded Aluminum Conductors, Coated Steel Supported (ACSS).

The strandings available are identical to those listed in ASTM specification B232.