An arrangement for controlling an automated system, having a number of sensors and actuators, in particular for controlling a railroad system. A programmable control unit runs a user program to process input data from the sensors and to generate control commands for the actuators. The sensors and the actuators are connected to a remote I/O unit, which is connected to the control unit via a communication network. The control unit and the I/O unit interchange data messages in order to transmit the input data and the control commands. The arrangement has a remote disconnection unit, which is coupled to the remote I/O unit independently from the input data and control commands. The control unit is designed to integrate specific verification data for the disconnection unit into the data messages for the I/O unit. The disconnection unit is designed to deactivate the I/O unit depending on the specific verification data.