摘要 |
Mitigation of faults in a telephone exchange, the faults being in the form of interruptions in calls in progress caused by brief voltage drops or failure of the AC voltage supply to the exchange. Failure of the AC supply, or a voltage drop in the stabilized Dc voltage is detected, and causes interruption of the program execution in the exchange. Depending on whether the fault has a duration greater or less than a given time, either all connections set up are released, or the connection state for the time before the occurrence of the fault is set up again. |