What is an ACSR Conductor : Types and Its Advantages

The term ACSR stands for “Aluminium Conductor Steel Reinforced is a stranded conductor including a number of aluminum wire layers on stimulated steel wire core. Here the steel wire core is a single wire that depends on the size. These are available in different galvanizations like class A, B & C for protecting the corrosion. In this kind of conductor, the quantity of aluminum & steel can be chosen depending on the capacity of current-carrying & mechanical strength based on the application. The recognition of these conductors can be done based on features like dependability, economy, economy, weight ratio, and positive strength. This article discusses an overview of what is an ACSR conductor, types, and their working.

What is the ACSR Conductor?

Definition: ACSR is a high-capacity stranded conductor which is mainly used for overhead power lines. The ACSR conductor design can be done like this, the outside of this conductor can be made with pure aluminum material whereas the inside of the conductor is made with a steel material so that it gives extra strength to give support to the weight of the conductor. As compared with aluminum, steel material has high strength, so the mechanical force can be applied over the conductor. The service life of the steel material used in the conductor can be extended by galvanizing or coating with another material. So that corrosion on the material can be prevented. Based on the type of ACSR conductor, the diameters of the steel & aluminium can be changed.

ACSR Conductors
ACSR Conductors

ACSR conductor sizing is, these are available in various sizes including single or numerous center steel wires. In general, a large amount of aluminium strand. Even though, there are some kinds of conductors available that have a large number of steel strands as compared with aluminum strands. The part of an ACSR can be recognized through its stranding.

ACSR Conductor Types

In energy transmission, copper conductors are used in many years back, but at present, AI conductors have replaced these copper conductors due to some reasons like not expensive as compared with copper, high diameter, etc. There are different types of ACSR conductors are available which include the following.

  • All Aluminium Conductor – AAC
  • Aluminium Conductor Aluminium Reinforce – ACAR
  • All Aluminium Alloy Conductors – AAAC
  • Aluminium Conductor Steel Reinforced – ACSR

All Aluminimum Conductor (AAC)

This conductor has low strength as well as extra sag per span length as compared with any type. So, it is used at the distribution level. The conductivity of this conductor is somewhat better at the distribution level. The cost of both the AAC & ACSR conductors are the same.

Aluminium Conductor Aluminium Reinforce (ACAR)

ACAR combines a number of aluminum alloy strands for providing a transmission conductor including excellent electrical & mechanical balance properties. These aluminum strands are covered with aluminum alloy wires. The core of the conductor includes the number of strands. The main benefit of this conductor is that all strands in the conductor are identical, thus allowing the conductor design with the best electrical & mechanical characteristics.


All Aluminium Alloy Conductors (AAAC)

This AAAC conductor construction is similar to AAC excluding the alloy. The strength of this conductor is equivalent to the ACSR type however, because of the nonexistence of steel it is less weight. The existence of alloy formation will make this conductor expensive. AAAC is used for longer spans because of the stronger tensile strength as compared with AAC. So it is utilized in the distribution level that is a river crossing. This conductor has low sag when compared with AAC. AAAC conductors are less in weight, so applicable for transmission & sub-transmission wherever less weight support structure is necessary like swamps, mountains, etc.

Aluminium Conductor Steel Reinforced (ACSR)

ACSR conductors are filled with steel material inside. The high strength ACSR conductors are applicable for overhead earth wires, installations relating extra-long spans & river crossings. These are manufactured with different tensile strengths. Because of the high diameter, a much higher radiance limit can be attained.


The ACSR conductor properties include the following.

  • Skin effect
  • Proximity effect
  • Hysteresis loss

Skin Effect

When the current flows through the conductor, the cross-sectional area of the conductor can be decreased through the skin effect. For AC, most of the current flow can be in between the outside & the deepness of the skin. It mainly depends on the frequency of the flow of current & the conductor properties. This reduced area of the conductor will increase the resistance because of the opposite relationship between the cross-sectional area of the conductor & resistance. The skin effect helps the conductor design because it causes to flow the current in the low-resistivity aluminum direction at the exterior of the conductor. To demonstrate the effect of this effect, the ASTM like the American Society for Testing & Materials standard includes the steel core conductivity while measuring the resistance of the AC & DC of the conductor.

Proximity Effect

Once the AC current flows through the conductors, then the flow of current in every conductor can be forced to smaller regions so this current flowing is called the proximity effect.

This effect is the outcome of a varying magnetic field that powers the flow of electric current in a conductor because of electromagnetic induction. Once AC supplies throughout an isolated conductor, then it makes a related alternating magnetic field in the region of it. This magnetic field will induce eddy currents within contiguous conductors and changes the total current distribution throughout them.

Hysteresis Loss

In the ACSR conductor, hysteresis losses mainly occur because of the atomic dipoles within the steel core. These losses are not attractive but it can be reduced with the help of aluminium layers which are in even position within the conductor.
The hysteresis loss is insignificant in this conductor including even no. of aluminium layers. For these conductors including an odd no. of aluminium layers but, a magnetization feature is utilized to calculate the AC resistance precisely. Because of the high hysteresis losses within the steel & associated core heating, the design of an odd-layer will have a low-capacity rating as compared with an even-layer design. All typical ACSR conductors are smaller than Partridge because they have simply a single layer because of their little diameters thus the hysteresis loss cannot be avoided.


The advantages of the ACSR conductor include the following.

  • ACSR conductor’s structure is plane
  • The capacity of transmission is high
  • These cables are distinguished by outstanding tensile power
  • Excellent performance
  • These are long-lived
  • They provide a great deal of flexibility

Thus, this is all about an overview of the ACSR conductor which includes a solid otherwise stranded steel core enclosed with aluminum strands. This conductor includes one or more aluminum wire layers which are covered with a huge strength of steel core. These are obtainable in an extensive range of steel that contains 0.5% to 0.85 % of carbon. Here is a question for you, what are the applications of the ACSR conductor?