The "linascope''-an echo-ranging type fault locator for high-voltage lines

The "Linascope," an electronic fault locator is described which uses an echo-ranging method for determining the location and nature of transmission line faults. This device has been used on open-wire telephone circuits for the location of various fault conditions, including open and short circuits, and high-resistance joints. Tests have been performed on high-voltage transmission lines which were removed from service for the purpose. Artificial faults applied at distances as great as 300 miles were detected. Open and short circuit faults are readily observed. Transposition points give slight echoes. The equipment has been used for inspecting live lines. In this application a high-frequency pulse is used which is coupled to the line by means of a high-voltage coupling capacitor. It is intended to use photographic recording gear with this instrument for the continuous inspection of live lines, in order to locate transient faults such as occur with lightning flashover of live-line insulators.