Aluminium Conductor Steel Reinforced
Encyclopedia
Aluminum conductor steel reinforced (or ACSR) cable is a specific type of high-capacity, high-strength stranded cable typically used in overhead power lines
. The outer strands are aluminum, chosen for its excellent conductivity, low weight and low cost. The center strand is of steel
for the strength required to support the weight without stretching the aluminum due to its ductility
. This gives the cable an overall high tensile strength.
ACSR cables are available in several specific sizes, with multiple center steel wires and correspondingly larger quantities of aluminum conductors. For example, an ACSR cable with 72 aluminum conductors that requires a core of 7 steel conductors will be called 72/7 ACSR cable.
The higher resistance of the steel core is of no consequence to the transmission of electricity since it is located far below the skin depth where essentially no AC current flows.
Overhead powerline
An overhead power line is an electric power transmission line suspended by towers or utility poles. Since most of the insulation is provided by air, overhead power lines are generally the lowest-cost method of transmission for large quantities of electric energy...
. The outer strands are aluminum, chosen for its excellent conductivity, low weight and low cost. The center strand is of steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
for the strength required to support the weight without stretching the aluminum due to its ductility
Ductility
In materials science, ductility is a solid material's ability to deform under tensile stress; this is often characterized by the material's ability to be stretched into a wire. Malleability, a similar property, is a material's ability to deform under compressive stress; this is often characterized...
. This gives the cable an overall high tensile strength.
ACSR cables are available in several specific sizes, with multiple center steel wires and correspondingly larger quantities of aluminum conductors. For example, an ACSR cable with 72 aluminum conductors that requires a core of 7 steel conductors will be called 72/7 ACSR cable.
The higher resistance of the steel core is of no consequence to the transmission of electricity since it is located far below the skin depth where essentially no AC current flows.