摘要 |
In an overhead electric transmission system in which an overhead conductor includes at least one optical fibre constituting part of an optical communication system, there is provided, at a tower along the system, an electrically conductive rod supported by and electrically insulated by an insulator from the cross-arm of the tower but electrically connected to earth through the primary winding of a step-down voltage transformer. The rod is substantially horizontal and substantially parallel to a group of overhead electric conductors suspended from the cross-arm by an insulator. The surface area of the metal rod and its position with respect to the group of current-carrying conductors of the system are such that electrical power for regenerators or other ancillary equipment of the optical communication system is provided across the secondary winding of the transformer, thereby affording simple and inexpensive means of providing such power. |