Carrier-current relaying and communication on the TVA system

Carrier pilot relaying and carrier-telephone communication have been installed to meet the difficult requirements of relaying and intrasystem communication on the extensive Tennessee Valley Authority system. Eight power-line carrier-telephone channels which can be interconnected at many points and carrier pilot relaying on 20 high-voltage transmission lines help to expedite the multipurpose operating procedures of the TVA. This article gives reasons for the selection of carrier relaying and communication and presents an analysis of their application, of the difficulties encountered, and of their over-all performance under service conditions.