| 摘要 |
PURPOSE:To protect overcurrents by installing a first element such as a filament and a second element such as a cathode and mounting a current transformer, through which two high-tension cables are penetrated, and an overcurrent detector supplied with the output currents of the current transformer. CONSTITUTION:Filament currents If are made to flow through a filament 2 through high-tension cables 26P, 26N, and currents Is made to flow between the filament 2 and a cathode 3 are made to flow through the high-tension cables 26P, 26N. Since magnitude is equalized and the direction of flow is opposed in filament currents If made to flow through the high-tension cable 26P and filament currents If made to flow through the high-tension cable 26N, a current transformer detects only currents Is at all times. The currents Is are at a low level on normalcy, but they are brought to large short-circuit currents when a discharge phenomenon is generated between the filament 2 and the cathode 3, and an overcurrent detector detects the short-circuit currents. |
