Corrosion detector for assessing the remaining life of old steel reinforced aluminium conductors

The durability of steel reinforced aluminium (ACSR) overhead line conductors is limited mostly by the corrosion of the steel core. A corrosion detector has been developed, operating on the nondestructive principle of measurement, to assess the degradation of the zinc galvanisation and to detect the corrosion of the steel core. After many laboratory measurements, the instrument was developed further for field usage on switched-off overhead lines. The corrosion detector is a mobile data logger, which can be rolled along the conductor. By the analysis of a measured voltage vector, different stages of the corrosion process can be detected.