Current sensor based on changes in magnetic or opto-magnetic material

摘要

A current sensor is based on the changes which take place in the magnetisation of a local region of magnetic or opto-magnetic data storage material when subjected to the field of a current-carrying conductor. A magnetic card (3) is positioned alongside the conductor (1) to be monitored and a ferro-magnetic shield (2) is folded to enclose the card (3) within a V-shaped aperture. The variable geometry of the assembly enables the sensitivity of response/current range of the sensor to be suited to the application and an excess current in the conductor (1) is detected by the pick-up of a scanning electromagnetic card reader.