| 摘要 |
PURPOSE:To secure the information of the fault occurring at the center unit to the holding center by connecting the automatic calling unit to the incoming exclusive circuit. CONSTITUTION:Automatic calling unit ACU is started through data unit D when the fault occurs, and then the telephone number information of telephone A in the holding center is sent. Unit ACU is connected to network control unit NCU1 via link LK2 to start exchange EX. And the dial pulse corresponding to the telephone number information of telephone A is sent out from unit ACU to be connected to telephone A via incoming exclusive circuit L1 and exchange EX. |
