steel-reinforced (ACSR) is a specific
type of high-capacity, high-strength stranded conductor typically used
in overhead power lines. The
outer strands are high-purity 1350 or 1370 aluminium alloy. chosen for its excellent conductivity, low weight and
low cost. The center strands are of steel for
the strength required to support the weight without stretching the aluminium
due to its ductility. This gives
the conductor an overall high tensile strength.