| 摘要 |
<p>PURPOSE:To allow the long term measurement of temperature at a live part while ensuring safety by protecting an optical fiber against high voltage. CONSTITUTION:Looped part 1a of an optical fiber 1 is contained in a metal case 3 from which end part of the optical fiber 1 is taken out and pulsating light is passed through the optical fiber 1 in order to detect temperature at a live part based on the intensity of Raman backscattered light. The case 3 is covered with a dielectric 2 such as silicon resin and electrically insulated from a heat plate 4 abutting directly on the live part. The metal case 3 is connected with a grounding lead wire 7 thus preventing application of voltage onto the optical fiber 1. The heat plate 4 is made of a good thermal conductor, e.g. copper, having a fixing hole 8 for fixing the heat plate 4 to a live part through bolts and nuts. The heat plate 4 has a partially exposed part 4a and the residual part is coated 2a with the dielectric 2 so that influence of ambient temperature is suppressed.</p> |
