Instrumentation control system

An instrumentation control system comprising:

• a plurality of input/output modules, wherein
• each input/output module of the plurality of input/output modules (i) is provided adjacently to and is connected to, via an analog line, a respective field device of a plurality of field devices, (ii) is configured to receive a signal from or transmit a signal to the respective adjacent field device, and (iii) includes a control logic unit configured to perform various control calculation processes for the respective field device;
• and
• a communication network connecting the plurality of input/output modules to each other by a communication line, wherein
• a first field device, of the plurality of field devices, is connected to and transmits a first signal to a first input/output module,
• a second field device, of the plurality of field devices, is connected to a second input/output module,
• the first input/output module includes an instrumentation module that transfers the first signal from the first field device, to the control logic unit included in the first input/output module, and the control logic unit executes a calculation process on the first signal and outputs a calculation result, as process data, via the communication network, to (i) the second input/output module, and (ii) a central monitoring control device,
• the second input/output module includes a control module and receives a signal from the central monitoring control device, receives the process data, from the instrumentation module of the first input/output module, executes a logic calculation on the received process data, and outputs a result of the logic calculation to the second field device connected thereto, and
• the central monitoring control device is connected to the communication network, monitors an operation state of each field device, and outputs a command for changing a control variable of the process data, to the control module of the second input/output module.