| 摘要 |
PURPOSE:To provide a safety device for an elevator which can restore easily and speedily by specifying the abnormal element of a converter and inverter consisting of the self arc extinguishing elements. CONSTITUTION:A self arc extinguishing element which constitutes a converter 2 and an inverter 4 is operated by the instruction of a microcomputer 8, and an ac motor 5 is driven to operation-control an elevator 12. The electric current which flows in the ac motor 5 is detected by the detectors 6a-6c, and taken into the microcomputer 8. In the microcomputer 8, the expected value of the electric current which is obtained through calculation and the detection value are compared, and when the difference exceeds a prescribed value, anomaly is judged, and an abnormal element is specified and stored in the prescribed judgement mode. Also the electric current detection value in each phase in this case is stored. |
