| 摘要 |
PROBLEM TO BE SOLVED: To find a time when a load protective relay detects the abnormality of a load and a reason why the abnormality is caused. SOLUTION: When a programmable controller 2 receives detection object data transmitted from a load protective relay 3, it shifts the memory content of a memory 2b and stores the detection object data in the leading area of the memory 2b in a state after the shifting process with calendar data has been outputted by a real time clock 2a and main circuit data. If a display request signal is given by a graphic operation panel 13, the data stored in a memory area Dm of the memory 2b are converted into display form data and given to the graphic operation panel 13 and displayed. |
