MAGNETIC FIELD DETECTION SYSTEM

摘要

A solid state sensor (1), such as a Hall effect device, is placed in close proximity to a current carrying conductor (2). A magnetic field (3) is generated by the current flowing in the conductor (2). A second sensor (4) is placed some distance away from (1) but residing in the same vertical plane, and inverted so that for current flowing out of conductor (2) its output goes negative. When the outputs at (1) and (4) are summed the combined output will only represent flux due to the conductor, as the two measurements due to any external fields will cancel out. Modified systems may be employed with additional sensors, particularly if used in association with a pair of conductors in a current carrying system. It then becomes possible to detect any tampering with the system.