| 摘要 |
PURPOSE:To surely evaluate the amount withstanding a surge caused by switching of a board to be tested by additionally providing a part to generate pseudo surge caused by switching of a circuit breaker. CONSTITUTION:For a grounding, short-circuit fault, etc., of a transmission line 3, the voltage and current are detected by a current transformer 4 and a potential transformer 5 to supply them respectively to input parts 6 of each board to be tested. The voltage and current inputted to the input part 6 are temporarily stored in sample/hold circuits 13. The hold circuits 13 which are provided in plural numbers are selected in order at a multiplexer 14 and fetched to a RAM 19. Data fetched to the RAM 19 are evaluated by a main processing unit 18 in accordance with the decision reference stored in a ROM 20 beforehand and the circuit breaker 2 is made to open as necessary. Whether the board to be tested is erroneously made to work or unwork by the surge caused by switching of the breaker 2 can be surely verified at the in-factory test without using the actual system as experimental means irrelevant to the scale and constitution of the system. |
