| 摘要 |
PURPOSE:To grasp accurately and efficiently error information by transmitting various abnormal information of a means for detecting an abnormal system and a terminal station to a control station controlling the entire system via the same transmission line as that for transmission data to discriminate which terminal station is faulty and to display the result centralizingly. CONSTITUTION:Data transmitted from a central controller is received by control sections 24a, 24b and 24c in a data transmission section 17 and transmitted to a 2 out-of-3 circuit 27 and a dissidence detecting section 28 in a common section 15 by digital output sections 25a, 25b and 25c. The circuit 27 compares three inputted digital signals and outputs two signals in the three signals to a control variable 30. The dissidence detection circuit 28 inputs three systems of output signals 32a, 32b and 32c and detects the dissidence between the a-system output and a b-system output, between the b-system output and a c-system output and between the c-system output and the a-system output by using NAND circuits 33a, 33b and 33c. The dissidence signal transmitted to a central controller 18 is outputted and displayed respectively by the systems. |
