| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a digital protective relay excellent in economy in which environmental preservation is taken into account by making it possible to limit a part being replaced or revised in design upon occurrence of failure or when enhancement of protective function is required. <P>SOLUTION: The digital protective relay 1 is provided with an analog input unit 2 for inputting the electric amount of an electric facility to be protected and performing A/D conversion, a unit 3 performing protective relay operation based on the electric amount inputted by the analog input unit 2, and an I/O unit 4 for inputting external information and outputting the results of protective relay operation. The analog input unit 2 and the operating unit 3 are connected through a serial transmission line (first transmitting section) 5 whereas the operating unit 3 and the I/O unit 4 are connected through a serial transmission line (second transmitting section) 6. The serial transmission lines 5 and 6 are constituted of wires or optical cables by well known technology. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
