An arithmetic operation device configuring a control apparatus includes: a communication circuit that is used for exchanging data with functional units through a communication line; a processor that is used for executing a user program executing at least one of an arithmetic operation process using data acquired from the functional units and a generating process of data to be transmitted to the functional units; and a monitoring circuit that is connected to the communication circuit and the processor. The monitoring circuit gives a notification from the communication circuit to the functional units on the basis of at least one of detection of shutoff of power supplied to the arithmetic operation device and reception of a preliminary notification before the shutoff of the power supplied to the arithmetic operation device, and the notification is used for executing a process according to shutoff of power supply to the arithmetic operation device.