Steel Supported ACSS Conductor Increased Current Rating For Overhead Transmission Line

Aluminum Conductor Steel Supported ACSS Conductor Low Voltage Bare Conductor

Quick Details

Packaging & Delivery

Packaging Details: New wooden drum, Reel, Circle or according to customer's request
Delivery Time: According to customer's request, usually 2-4 weeks.

Description

Shaped Wire Compact Concentric-Lay-Stranded Aluminum Conductor, Steel-Supported (ACSS/TW) is a concentrically stranded conductor with one or more layers of trapezoidal shaped hard drawn and annealed 1350 aluminum wires on a central core of steel. ACSS/TW can either be designed to have an equal aluminum cross sectional area as that of a standard ACSS which results in a smaller conductor diameter maintaining the same ampacity level but reduced wind loading parameters or with diameter equal to that of a standard ACSS which results in a significantly higher aluminum area, lower conductor resistance and increased current rating.
ACSS/TW is designed to operate continuously at elevated temperatures, it sags less under emergency electrical loadings than ACSR/TW, excellent self-damping properties, and its final sags are not affected by long- term creep of aluminum. ACSS/TW also provides many design possibilities in new line construction: i.e., reduced tower cost, decreased sag, increased self-damping properties, increased operating temperature and improved corrosion resistance. The coating of steel core is selected to suit the environment to which the conductor is exposed and operating temperature of the conductor.

Service Performance

1. High tensile strength
2. Long life
3. Light in weight
4. Suitable for high as well as extra high overhead

Construction

ACSS is a composite concentric-lay stranded conductor. Steel strands form the central core of the conductor with two or more layers of aluminum 1350-O wire stranded around it. The steel core carries most or all of the mechanical load of the conductor due to the "O" temper (fully annealed or soft) aluminum. Steel core wires are protected from corrosion by a zinc-5% aluminum-mischmetal alloy coating. For aluminum-clad (AW) ACSS, please refer to the ACSS/AW catalog sheet. Corrosion protection should be selected to suit the environment to which the conductor will be exposed.

Features

ACSS conductors are preferred over ACSR conductors for specific transmission line applications:
ACSS has at least 63.0% IACS conductivity due to their “dead-soft” (fully annealed) aluminum strands.
For the same reason, ACSS cables can be operated at temperatures of maximum 250 °C without loss of strength. Since the mechanical tension applied to the aluminum strands is low, the ACSS self damping characteristic is high. This allows ACSS cables to be installed at high unloaded tensions without the need for separate Stockbridge dampers.
— ACSS conductors can be operated up to 250 °C vs. the maximum operating temperature for an ACSR conductor does not exceed 100 °C.
ACSS conductors are prone to resist the effects of aeolian vibration due to very little or no mechanical load on the annealed aluminum wires.
Long term creep is not a factor when designing with ACSS conductors. In addition, use of ACSS/TW with the equal area design allows equal ampacity in a conductor with approximately 10% smaller diameter over a standard ACSS with same area. This smaller diameter of equal area ACSS/TW conductors helps reduce the effects of ice and wind loading on the conductor.
Alternatively, use of ACSS/TW with equal diameter design provides a conductor in which the aluminum area is increased by approximately 20% – 25% over a standard ACSS with same diameter. This increase
in the cross-sectional area of the conductor reduces its ac resistance by about 15% – 20% and thus, increases its current carrying capacity by about 10%.

Advantages

1. Reduced drag characteristics
2. Excellent self-damping properties
3. Improved current carrying capacity
4. Low wind and ice loading parameters
5. long term creep of aluminum doesnot affect final sag

Application

ACSS is used for overhead distribution and transmission lines. It is designed to operate continuously at elevated temperatures up to 250°C without loss of strength; it sags less under emergency electrical loadings than ACSR; it is self-damping if prestretched during installation; and its final sags are not affected by long term creep of aluminum. The advantages make ACSS especially useful in reconductoring applications requiring increased current with existing tensions and clearances, new line applications where structures can be economized because of reduced conductor sag, new line applications requiring high emergency loadings, and lines where aeolian vibration is a problem.

Specification

• B 500 Metallic Coated Stranded Steel Core for Use in Overhead Electrical Conductors.
• 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
(ACSR).
• B803 High-Strength Zinc-5% Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Use in Overhead Electrical
Conductors.
• B856 Concentric-Lay-Stranded Aluminum Conductors, Coated Steel Supported (ACSS).
• B958 Extra-High-Strength and Ultra-High-Strenght Class A Zinc-5% Aluminum-Mischmetal Alloy-Coated Steel Core Wire for Use in Overhead Electrical Conductors.
The strandings available are identical to those listed in ASTM specification B232.