| 摘要 |
PURPOSE:To virtually eliminate the stop time of a system as a whole, by securing an execution of the working test for the data station to be established newly while operating an existing data station. CONSTITUTION:The programable controller PC1 transmits the optical signal containing the wavelengths lambda1, lambda2 for both on-line and test to the using transmission line 10 from the data station ST1. This optical signal is sent to the station ST4 where only lambda1 is returned to the standby transmission line 11, and lambda2 is transmitted to the station ST7 via the line 10. At the station ST5, the lambda2 sent from the ST7 and the lambda1 from the ST6 are synchronized together to be sent to the line 10. This synthesized signal returns to the station ST1 to be put into the controller PC1. As a test program for the test channel is incorporated previously into the PC1, other data stations are kept on. Thus a working test is possible for the station PC7. |
