| 摘要 |
PROBLEM TO BE SOLVED: To realize a digital protective relay by which the time of accident occurrence can be defined without including a real time clock IC whose application frequency is low. SOLUTION: Time measurement is started according to relay operation (step S3). When a manager inputs a time manually (step S4), the above measured time is deducted from the inputted time (step S5). Consequently, the time when the accident was generated is specified and outputted (step S6). The time measurement is not continued all the time but may be started when a relay is operated, so that a time measuring means can be realized with a software. |
