Optical-fiber communications for electric power companies in Japan

The Japanese electric power companies have long been interested in the optical fiber communication-system features, such as non inductivity, high-insulation property, large transmission capacity etc. Since 1974 they have been conducting field experiments utilizing optical-fiber communications for transmitting power-system protection, supervision, and control data. Based on these works, six Japanese electric companies have installed nine optical fiber communication systems since 1978, and their performance records are fully satisfactory.