| 摘要 |
A plant control system comprises a process computer (1) for controlling a plant, a PLC (2) interposed between the process computer (1) and plant equipment (3), and a general-purpose PC (7) for performing arithmetic processing based on arithmetic data received from the PLC (2) and transmitting the arithmetic result data to the PLC (2). The functions of the PLC (2) and the general-purpose PC (7) are divided such that the PLC (2) executes a sequential control logic process whereas the general-purpose PC (7) executes a complicated arithmetic process. In addition, the arithmetic result data output from the general-purpose PC (7) is always shared with the PLC (2) and a consistency of the arithmetic result data is checked in the PLC (2). This makes it possible to divide, by introducing a general-purpose personal computer (general-purpose PC) into a plant control system, the functions of a programmable logic controller (PLC) and the general-purpose PC and to ensure reliability in an industrial application of the general-purpose PC, for example, at the view point of punctuality. |
