UK power utilities experiences with optical fibres

Summary form only given. Optical telecommunications systems have been installed for business ventures outside the needs of the utility itself. A specific network for this application is described along with the reasons for the optical technology adopted, and experience with this application and earlier applications of the same technology for core network use. A brief description is given of a system to change the existing earthwires on double-circuit, 400 kV lines without switching circuits out or providing additional ground protection. The phenomenon of dry-band arcing is described and its apparent vagaries are demystified. Advice is given on how to minimise the risk of damage, and the latest developments are discussed, with results of a long term trial mounted in Scotland. Reasons for the choice of all-dielectric self-supporting cables within a UK Utility against the other options of optical ground wire or Externally Attached systems with the power system as a carrying medium are discussed