Detection of electrolytic corrosion on steel-cored aluminium conductors

Steel-cored aluminium conductors in coastal districts are sometimes subjected to a severe form of electrolytic corrosion which can cause the conductor to break when there is a high load current. The effects of this corrosion are usually very local and are difficult to detect without special equipment. The paper describes a trolley-mounted gauge that can be towed along an unenergized conductor by an operator on the ground, who is warned when a bulge, which is the external manifestation of this corrosion, is traversed. With only one cord thrown over the conductor, it is possible for the operators on the ground to raise the detector to the conductor, secure it in the working position, release it and lower it to earth.