System with an electrical apparatus

A system includes an electrical apparatus and a connecting device. The electrical apparatus comprises a control unit, a first interface device and a second interface device. A wire-bound first communication path is provided between the control unit and the connecting device via the first interface device and a second communication path is provided between the control unit and the second interface device. The system further includes a coupling device that can be set into a first coupling state and into a second coupling state. The first communication path is led through the coupling device in the first coupling state and is interrupted in the coupling device in the second coupling state. The control unit detects an attack on the system via the second interface device and, in the event of a detected attack, sets the coupling device from the first coupling state into the second coupling state.