| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable the defective part of a conductor in a hot-line state to be detected, reduce generation of dislocation of a sensor and detection error due to unblanced insulator thickness, and improve detecting sensitivity of the defective part such as breaking of element wire. SOLUTION: A magnetic field sensor 2 and a distance sensor 7 are arranged in parallel in the lengthwise direction of an insulated wire 1, a distance up to the surface of a conductor 1a is measured, the induced voltage of the magnetic field sensor 2 based on the magnetic field generated at letting flow alternating current is computed from the distance data of the distance sensor 7, this computed result is compared with the induced voltage actually detected by the magnetic field sensor 2, and hence existence of abnormality of the concuctor 1a is discriminated, by whether difference is generated between both or not.</p> |
