| 摘要 |
<p>PURPOSE:To improve the utility of a communication system by allowing each terminal station device to measure a time when a transmitted signal is fed back from a reflected point, inform this time to a supervisory device and allowing the supervisory device to use the time and detect a line faulty location. CONSTITUTION:When a control section 8 of each terminal station device 5 receives a transmitted telegraphic message addressed to itself, a count of a counter section 20 is read, a telegraphic message informing the value and the own device address is constituted, and the result is transmitted to the supervisory device 4. A control section 10 of the device 4 holds a pair of the time value and the terminal station device address. When the required information is received, the control section 10 compares the stored time values, constitute an arrangement list arranging terminal station device addresses corresponding in a prescribed order and stores the list to a storage section 21. When no response comes from, e.g., a terminal station device 5-2, the supervisory device 4 references the said arrangement list, reads the address of a terminal station device 5-3, and transmits a telegraphic message for diagnosis to the terminal station device 5-3. When a normal response is obtained from the device 5-3, it is discriminated that the fault exists in the terminal station device 5-2. When no response comes also from the device 5-3, it is discriminated that the fault exists between corresponding couplers.</p> |
