| 摘要 |
PURPOSE:To enable snow to be removed without stopping the operation of a breaker by feeding current to a section for generating heat electrically when deflection on an operating box due to the fallen snow exceeds a specified value. CONSTITUTION:A deflection gauge is fitted on a position where deflection on the upper surface of an operating box 1 is maximized, and a sheathed heater 12 is firmly fitted on tank 2 in the longitudinal direction with a metallic band 13. The input of deflection signal 31 detected by the deflection gauge 11 is entered into a comparator 23 as output signal 32 by an amplifier 22. In this case, when the signal 32 exceeds the reference value of deflection corresponding with the level of specified fallen snow, then the output of working signal is generated and a thyristor 24 is turned ON. Then, from a DC power source 28, current flows to the working coil 25 of a relay, and a contact 26 is turned ON, and the contact 27 of another circuit is turned ON. Then, from an AC power source 29, current flows to a heat generator 30 for forming a heat generating section, and the melting of snow is started. Then, fallen snow on a bushing 3 is dropped, and the snow is continuously melted until the danger of insulating destruction is eliminated. |
