The effects of wind, snow and ice on optical fibre systems on overhead line conductors

The problems created by the effects of wind, snow and ice loadings on overhead line conductors have been studied for many years. Dampers are used to control aeolian vibration and galloping and various devices are in use to attempt to restrict heavy snow/ice loads. However, in addition to these dedicated devices, many networks are being used to transmit data using a variety of optical fibre systems. These include fibres contained within metal conductors and fibres wrapped externally onto the conductors. Fibre optic systems are also used in a self-supporting mode known as ADSS. EA Technology has been involved over the last eight years in the remote monitoring of test spans and samples of overhead line conductors in the UK in areas chosen for their severe weather. The sites are unmanned and regularly suffer gales, blizzards and severe icing conditions. These sites were therefore ideally suited to the investigation into the effects of these conductor mounted devices on the performance of the line. This paper details the optical fibre systems, the test sites and their monitoring techniques and the results obtained