| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a remote supervision and control system provided with a means for modifying internal clocks of a plurality of slave station devices which are connected by a communication line network in which a data residence time sequentially changes, have the internal clocks and are scattered with reference to a master station master clock and synchronizing the internal clocks of the slave station devices. <P>SOLUTION: A slave station device 8 adds a slave station transmitting time TK1 of an internal clock to a data response signal transmission time. The master station device 1 adds a master station receiving time TO2 of a data response signal and a master station transmitting time TO3 of a response arrival confirmation signal with a fixed data length. The slave station device 8 calculates a data residence average time t5 on the basis of a slave station receiving time TK4, calculates a deviationΔt between the master station master clock 2 and a slave station internal clock 12, and modifies the internal clock 12 to synchronize the times if the deviation exceeds a prescribed value. This enables time synchronization that corresponds to the state of the communication line network 7, can simplify procedures and can perform integrated equipment monitoring of a state change time of monitoring target equipment 14 detected by each slave station device 8 and accumulated measurement data with the time. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
