A control system for electrically controlled installations, comprising at least one control device for monitoring and/or controlling the installation and/or installation components, at least one portable, mobile hand-held terminal for displaying information and for the input of control commands by an operator, wherein the at least one portable, mobile hand-held terminal is provided with at least one manually actuatable safety switching element, with which safety switching element a lighting device having at least one lighting means is associated, and, between the safety switching element of the at least one portable, mobile hand-held terminal and the at least one control device or a separately formed safety controller, a signal connection, which may be coupled or released as needed, wherein the control system is configured for transferring the installation or one or more installation components into a safe state upon presence of a coupled signal connection and upon manual actuation of the safety switching element, and wherein the control system is configured for activating the lighting device upon presence of a coupled signal connection and for deactivating the lighting device upon presence of a released signal connection, wherein it comprises at least one lighting control device, which is configured for the electrically and/or electronically controlled adaptation of a visually perceptible light intensity of the lighting device upon presence of a coupled signal connection between the safety switching element of the at least one portable, mobile hand-held terminal and the at least one control device or the safety controller. characterized in that at least one detection means for monitoring user activities is provided on the at least one portable, mobile hand-held terminal, which detection means is configured for signaling a detected presence or a detected absence of user activities with respect to the at least one lighting control device, and that the at least one lighting control device is configured for the electrically and/or electronically controlled adaptation of the visually perceptible light intensity to a first low level upon presence of a coupled signal connection and during a signaling of a presence of user activities, and is configured for the electrically and/or electronically controlled adaptation of the visually perceptible light intensity to a second level that is higher in comparison with the first level, upon presence of a coupled signal connection and during a signaling of an absence of user activities. at least one control device for monitoring and/or controlling the installation and/or installation components, at least one portable, mobile hand-held terminal for displaying information and for the input of control commands by an operator, wherein the at least one portable, mobile hand-held terminal is provided with at least one manually actuatable safety switching element, with which safety switching element a lighting device having at least one lighting means is associated, and, between the safety switching element of the at least one portable, mobile hand-held terminal and the at least one control device or a separately formed safety controller, a signal connection, which may be coupled or released as needed, wherein the control system is configured for transferring the installation or one or more installation components into a safe state upon presence of a coupled signal connection and upon manual actuation of the safety switching element, and wherein the control system is configured for activating the lighting device upon presence of a coupled signal connection and for deactivating the lighting device upon presence of a released signal connection, wherein it comprises at least one lighting control device, which is configured for the electrically and/or electronically controlled adaptation of a visually perceptible light intensity of the lighting device upon presence of a coupled signal connection between the safety switching element of the at least one portable, mobile hand-held terminal and the at least one control device or the safety controller. characterized in that at least one detection means for monitoring user activities is provided on the at least one portable, mobile hand-held terminal, which detection means is configured for signaling a detected presence or a detected absence of user activities with respect to the at least one lighting control device, and that the at least one lighting control device is configured for the electrically and/or electronically controlled adaptation of the visually perceptible light intensity to a first low level upon presence of a coupled signal connection and during a signaling of a presence of user activities, and is configured for the electrically and/or electronically controlled adaptation of the visually perceptible light intensity to a second level that is higher in comparison with the first level, upon presence of a coupled signal connection and during a signaling of an absence of user activities.