Measuring wear of a power line

A standard method of providing power to an electric locomotive comprises an overhead power line from which power is transmitted to the locomotive through a pantograph. However, the overhead power line is gradually worn by the passage of pantographs. The present invention provides a way of measuring the wear caused by the passage of pantographs and comprises scanning means (100) for generating information corresponding to the periphery of the power line. Processing means (112) are coupled to the scanning means (100) in order to measure the thickness of the power line and the wear of the power line from the information corresponding to the periphery of the power line. It is thus advantageously possible to very accurately measure wear of the power line. The present invention also facilitates digital recording of measurements and does not require the apparatus to be in physical contact with the power line.