Since all the strands are the same diameter, one can show that the innermost layer always consists of 6 strands, the second layer of 1. Non Homogeneous Conductors: ACAR (Aluminum Conductor Alloy Reinforced)ACSR (Aluminum Conductor Steel Reinforced)ACSS (Aluminum Conductor Steel Supported)AACSR (Aluminum Alloy Conductor Steel Reinforced. In a 3. 0/7. ACSR conductor the aluminum and steel strands are of the same diameter. In a 3. 0/1. 9ACSR they are not. Within the core or within the outer layers, however, the number of strands always increases by 6 in each succeeding layer. Thus, in 2. 6/7 ACSR, the number of layers in the inner layer of aluminum is 1. Categories of Overhead Conductors. VR (Vibration Resistance)Non- Specular. ACSR / SD. The thermal coefficient of expansion is greater than that of ACSR. As compared to conventional ACSR, lighter weight, comparable strength & current carrying capacity, lower electrical losses and superior corrosion resistance have given AAAC a wide acceptance in the distribution and transmission lines. Features. High strength to weight ratio. Better sag characteristics. Improved electrical properties. Excellent resistance to corrosion. Specifications. Higher Tensile Strength. Excellent Corrosion Resistance. Good Strength to Weight Ratio. Lower Electrical Losses. Moderate Conductivity –5. 48 Electric Utility TransPowrTypes of Conductors Aluminum has replaced copper as the most common conductor metal for overhead transmission (Why?). In general, the types of conductors. Temperature of bare overhead conductors. The numerical study is performed with the help of the commercial code FLUENT-ANSYS that. DOE-STD-1090-2007 7-5 Chapter 7 Overhead and Gantry Cranes operating ropes if manual controllers are used, or near the pendant push-button station if magnetic. Southwire Overhead Conductor Manual Pdf VR2 Conductor Installation Guide PDF. IACSTypical Application. Transmission and Distribution applications in corrosive environments, ACSR replacement.(3) ACAR (Aluminum Conductor Al. Alloy Reinforced)Aluminum Conductor Alloy Reinforced (ACAR) is formed by concentrically stranded Wires of Aluminum 1. Aluminum- Magnesium- Silicon (Al. Mg. Si) Alloy core. The number of wires of Aluminum 1. Al. Mg. Si alloy depends on the cable design. Lecture 9: Transmission lines Instructor. An overhead transmission line usually consists of three conductors or bundles of. Types of Overhead Conductors Properties of Overhead Bare Conductors: Current Carrying Capacity Strength Weight Diameter Corrosion Resistance Creep Rate. Even though the general design comprises a stranded core of Al. Mg. Si alloy strands, in certain cable constructions the wires of Al. Mg. Si Alloy strands can be distributed in layers throughout the Aluminum 1. ACAR has got a better mechanical and electrical properties as compared to an equivalent conductors of ACSR,AAC or AAAC. A very good balance between the mechanical and electrical properties therefore makes ACAR the best choice where the ampacity , strength , and light weight are the main consideration of the line design. These conductors are extensively used in overhead transmission and distribution lines. Features. Improved strength to weight ratio. Improved mechanical properties. Improved electrical properties. Excellent resistance to corrosion Specifications. Balance of Mechanical & Electrical. Excellent Corrosion Resistance. Variable Strength to Weight Ratio. Higher Conductivity than AAACCustom Designed, diameter equivalent to ACSR most common. Typical Application. Used for both transmission and distribution circuits.(3) AACSR – Aluminum Alloy Conductor Steel Reinforced. AACSR is a concentrically stranded conductor composed of one or more layers of Aluminum- Magnesium- Silicon alloy wire stranded with a high- strength coated steel core. The core may be single wire or stranded depending on the size. Core wire for AACSR is available with Class A, B or C galvanizing; or aluminum clad (AW). Additional corrosion protection is available through the application of grease to the core or infusion of the complete cable with grease. Features. Offers optimal strength for line design. Improved strength to weight ratio. Ideal for extra long spans and heavy load conditions. Excellent resistance to corrosion(4) ACSS – Aluminum Conductors Steel Supported. ACSS is a composite concentric- lay stranded conductor with one or more layers of hard drawn and annealed 1. In an ACSS ,under normal operating conditions, the mechanical load is mainly derived from the steel core as aluminum in fully annealed stage does not contribute much towards the mechanical strength. Steel core wires are protected from corrosion by selecting an appropriate coating of the wire like galvanizing, mischmetal alloy coating or aluminum clad. The type of coating is selected to suit the environment to which the conductor is exposed and operating temperature of the conductor. ACSS are suitable for operating at high temperature without losing the mechanical properties. The final sag- tension performance is not affected by the long term creep of aluminum. Features. Improved conductivity. High current carrying capacity. Very low sag at high temperature. High degree of immunity to vibration fatigue. Better self damping property(6) ACCC – Aluminum Conductor Composite Core. Aluminum Conductor Composite Core (ACCC) is a concentrically stranded conductor with one or more layers of trapezoidal shaped hard drawn and annealed 1. Carbon and glass fiber composite. The ACCC Conductor uses a carbon fiber core that is 2. This allows with the help of trapezoidal shaped strands the ability to increase the conductor’s aluminum content by over 2. Features. Excellent Sag properties. Increased current carrying capacity. High operating temperature. Excellent strength to weight ratio. Highly energy efficient.(7) ACSR (Aluminum Conductor Steel Reinforced)Aluminum Conductor Steel Reinforced (ACSR) is concentrically stranded conductor with one or more layers of hard drawn 1. H1. 9 aluminum wire on galvanized steel wire core. The core can be single wire or stranded depending on the size. Steel wire core is available in Class A ,B or Class C galvanization for corrosion protection. Additional corrosion protection is available through the application of grease to the core or infusion of the complete cable with grease. The proportion of steel and aluminum in an ACSR conductor can be selected based on the mechanical strength and current carrying capacity demanded by each application. ACSR conductors are recognized for their record of economy, dependability and favorable strength / weight ratio. ACSR conductors combine the light weight and good conductivity of aluminum with the high tensile strength and ruggedness of steel. In line design, this can provide higher tensions, less sag, and longer span lengths than obtainable with most other types of overhead conductors. The steel strands are added as mechanical reinforcements. ACSR conductors are recognized for their record of economy, dependability and favorable strength / weight ratio. ACSR conductors combine the light weight and good conductivity of aluminum with the high tensile strength and ruggedness of steel. In line design, this can provide higher tensions, less sag, and longer span lengths than obtainable with most other types of overhead conductors. The steel strands are added as mechanical reinforcements. The cross sections above illustrate some common stranding. The steel core wires are protected from corrosion by galvanizing. The standard Class A zinc coating is usually adequate for ordinary environments. For greater protection, Class B and C galvanized coatings may be specified. The product is available with conductor corrosion resistant inhibitor treatment applied to the central steel component. Features. High Tensile strength. Better sag properties. Economic design. Suitable for remote applications involving long spans. Good Ampacity. Good Thermal Characteristics. High Strength to Weight Ratio. Low sag. High Tensile Strength. Typical Application. Commonly used for both transmission and distribution circuits. Compact Aluminum Conductors, Steel Reinforced (ACSR) are used for overhead distribution and transmission lines.(8) Trap Wire Constructions. AAC/TW (Trapezoidal Shaped 1. H1. 9 Aluminum Strands)ACSR/TW (Trapezoidal Shaped 1. H1. 9 Aluminum Conductor - Galvanized –Zinc or AW Coated Steel Core Wires)ACSS/TW (Trapezoidal Shaped 1. O Aluminum Conductor- Zinc –5% Mischmetal Aluminum Alloy or AW Coated Steel Core wires)Comparison of ACSR/TW Type Number with Equivalent Stranding of ACSRType Number Conventional ACSR Stranding. The equivalent stranding is that stranding of conventional ACSR that has the same area of aluminum and steel as a given ACSR/TW type. The ACSR/TW type number is the approximate ratio of the area of steel to the area of aluminum in percent.(8- a) ACSR/AS – Aluminum Conductor, Aluminum Clad Steel Reinforced. ACSR/AS or ACSR/AWare concentrically stranded conductors with one or more layers of hard drawn 1. H1. 9 aluminum wires on Aluminum Clad steel wire core. The core can be single wire or stranded depending on the size. The mechanical properties of ACSR/AS conductors are similar to ACSR conductors but offers improved ampacity and resistance to corrosion because of the presence of aluminum clad steel wires in the core. These conductors are better replacement for ACSR conductors where corrosive conditions are severe. Features. Good mechanical properties. Improved electrical characteristics. Excellent corrosion resistance. ACSS/AW – Aluminum Conductors –Aluminum Clad Steel Supported. ACSS/AW or ACSS/AS is a composite concentric- lay stranded conductor with one or more layers of hard drawn and annealed 1. In an ACSS/AW ,under normal operating conditions, the mechanical load is mainly derived from the steel core as aluminum in fully annealed stage does not contribute much towards the mechanical strength. Aluminum Clad steel has got an excellent resistance towards corrosion. ACSS/AW are can be safely operated upto 2. C continuously without losing the mechanical properties. The final sag- tension performance is not affected by the long term creep of aluminum. Features. Improved conductivity. High current carrying capacity. Suitable for high temperature. Excellent corrosion resistance. Very low sag at high temperature. High degree of immunity to vibration fatigue. Better self damping property(8- c) ACSR/TW – Trapezoidal Shaped 1. H1. 9wire Aluminum Conductor, Steel- Reinforced. Shaped Wire Compact Concentric- Lay- Stranded Aluminum Conductor, Steel- Reinforced (ACSR/TW) is a concentrically stranded conductor , made with trapezoidal shaped 1. H1. 9 wires over a high strength steel core. There are two possible design variants.
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