| 摘要 |
PURPOSE:To reconstitute the system quickly, in switching the existing device into a spare device due to a failure, by taking the spare device of communication link as operating state even during waiting, i.e., hot state. CONSTITUTION:Spare digital trunks DTC1, DTR1 and a spare circuit TL1 are in the same operating state as the existing state, i.e., in hot state, and spare communication controllers CCUC1, CCUR1 are repeated for the test operation to confirm the normality. In switching the existing device into the spare device, selectors SELC, SELR of both controllers MPR, RNP are respectively controlled to switch the communication controllers. In time division channel devices TDNWC, TDNWR, set telephone channels 1-6, 1'-6' are reset to be corresponded with the existing and spare systems. |
