Flat pressure cable

The flat pressure cable has a fully-impregnated dielectric which is maintained under a positive pressure by means of a self-contained flexible membrane provided by a specially reinforced lead sheath. A review is given of the history of the development of the cable as well as the construction and the principles on which the cable is designed. The design of the accessories is also considered, and the methods for deriving the current rating of the cable are described. The results of electrical tests show that the cable is suitable for transmission of electrical energy at the highest voltages. Operational experience shows the cable to be completely satisfactory, both electrically and mechanically. Future development of the cable with aluminium sheath and for transmission at direct voltages is discussed. The cable has been used extensively in Europe for both land and submarine use, and to date 109 miles of 3-core cable have been installed.