| 摘要 |
PURPOSE:To find the staining of an insulator in its early stage by connecting the ground side of the insulator to a steel tower through a conductor, and detecting the staining of the insulator from a leak current which flows through the conductor. CONSTITUTION:An insulator string 10 to which the conductor 11 and a single- mode optical fiber 12 are fitted is fitted to the steel tower 3 selected so as to detect the staining of an insulator 1. The conductor 11 is coiled and connected at one terminal 11a to the cap 1a of the ground-side insulator 1 and to the steel tower 3 at the other terminal 11b; and the single-mode optical fiber 12 is run through the coiled conductor 11 and both its terminals are connected to the detecting device body provided at a proper position of the steel tower 3. When the insulator 1 is stained more and a leak current flowing through the conductor 11 increases, magnetostriction effect occurs in a magnetostrictive material 13 such as an Ni-Co alloy covering the optical fiber 12, and consequently the optical fiber 12 is strained axially, so that the light beam propagating in the optical fiber shifts in phase. |
