LOCATING A GROUNDING FAULT IN ELECTRICAL EQUIPMENT

摘要

This invention concerns a system and an apparatus for locating a grounding fault on electric power equipment such as a power cable (11). Optomagnetic sensors (12a, 12b) are installed in spaced relation at each end of a section (L) of the cable (11). Signals from the optomagnetic sensors are transmitted to associated light-electricity conversion circuits (14a, 14b) by means of associated optical fiber cables (13a, 13b). A discrimination circuit (15) determines whether or not a grounding fault has occurred, and where it has occurred, based on the output signals of the light-electricity conversion circuits (14a, 14b). The determination is based on the magnetic level difference or phase difference between the latter output signals, or on a combination of the two.