ACSR – Aluminium Conductor Steel Reinforced


Aluminium Conductor Steel Reinforced can be manufactured to different strengths by requirement. The conductor is constructed from a solid steel core, surrounded by aluminium stranding. The solid steel core is strong yet ductile, while the outer stranding of aluminium gives excellent conductivity with a low weight and low cost. The ACSR conductor is available in a range of steel strengths from as little as 6% up to 40%. The stronger the steel percentage, the more arduous tasks it can take on; the highest strength conductors are used as overhead wires, for river crossings, and any installations which require a particularly long span without support.

ACSR also has the double benefit that as well as being high strength, it is also lightweight. ACSR conductors have a higher diameter than AAC and AAAC due to their steel core, and due to this they can obtain a higher corona limit, giving the advantage for high voltage overhead lines. ACSR is also used for local distribution, suspended from wooden poles or other alternative methods.

Selection of conductor size, type and strength should take into account factors such as electrical load, voltage regulation, and corona losses. Environmental conditions such as ice and wind loading, extreme temperatures and vibration should also be considered.



ACSR, a non-homogenous conductor, is a concentric-lay stranded conductor made from round aluminium EC wires and round, coated steel core wire(s). Several combinations of aluminium and steel strands and layers are available when designing ACSR conductors for overhead lines. Commonly used sizes are included here. Class A zinc coating (ACSR/GA2) is usually adequate for ordinary environments to protect the steel core wires from corrosion.


ACSR conductors are manufactured in accordance with the following Standards:

  • British Sizes     BS 215
  • British Sizes     BS EN 50182
  • IEC Sizes     IEC 61089
  • American Sizes     ASTM B 232
  • Canadian Sizes     CSA C 49
  • German Sizes     DIN 48 204


The favorable strength/weight ratio, achieved by the lightweight, strong conductivity of aluminium coupled with the high tensile strength of steel, makes ACSR conductors a preferred choice for overhead power transmission and distribution projects.
Steel strands provide mechanical reinforcement to handle higher line tensions, reduce sag, and achieve longer span lengths.
ACSR conductors are also recognized for their dependable performance under adverse weather conditions.