MULTIPLEXING CONTROL SYSTEM

PROBLEM TO BE SOLVED: To execute the test of a multiplexing control system during a plant operation.SOLUTION: The multiplexing control system includes: a plurality of control devices 108 to 110 constituted of input parts 307 to 309 to which signals from sensors 101 to 103 are input, arithmetic parts 120 to 122 for performing an arithmetic operation by the input signals and output parts 310 to 312 for outputting the arithmetic results; and an output processing part 114 for processing signals output from the plurality of control devices, and for outputting one control signal to a control object 116. The multiplexing control system includes: first input signal switching parts 201 to 203 disposed in a cable between each control device and the output processing part; a first output signal switching part 209 disposed in a cable between the output processing part and the control object; and a tester 207 for outputting a simulation signal via the first input signal switching part to the output processing part, and for receiving an output signal corresponding to the simulation signal via the first output signal switching part.