| 摘要 |
PURPOSE:To enable time setting of the sub-station clock in accordance with the main station clock without being affected by the time delay in communication line connecting the clocks by correcting a time shift between main station and sub-station and setting the time of the main station at the sub-station. CONSTITUTION:Provided are a first means to send the first data from a main station M to sub-stations S1-Sn at time Ta, a second means to measure the receiving time Tb of the first data at the sub-stations S1-Sn, a third means to send back this time Tb as the second data to the main station M, a fourth means to measure the receiving time Tc of the returned second data at the main station M, a fifth means to eliminate the delay time in the communication line based on the relation between the times Ta-Tc and to calculate the time shift between the main station S and the sub-stations S1-Sn as the correction time, and a sixth means to correct the time of the sub-stations S1-Sn based on the correction time, By this, time setting is possible without being affected by the time delay in the communication line. |
