A control system (1) for technical installations (2), comprising
- at least one stationary control device (7) with input and output interfaces for establishment of line connections to a technical installation (2) to be controlled,
- at least one electronic manual operator-control instrument (9) that can be carried and used in mobile manner by an operator-control person (11) for influencing and observation of workflows and states, based on control technology, of the control system (1) or respectively of a technical installation (2) connected thereto,
- which manual operator-control instrument (9) is provided with a wireless communication interface (16) using control technology and also a communication interface (18) that can be established using control technology via a connecting cable (17), with which communication interfaces (16, 18) an integration of the manual operator-control instrument (9) into the control system (1) using data technology is respectively possible,
- at least one safety switching element (15) that can be actuated by an operator-control person (11) on the manual operator-control instrument, which safety switching element (15) is provided at least for a termination of control commands or movement sequences that are potentially critical to safety,
- a safety switching circuit (19), which is closed in the normal state, which safety switching circuit (19) can be transferred into an interrupted or opened state for avoidance of a hazardous state and is provided for disconnection of potentially hazardous movements or sequences of an activated technical installation (2) or for establishment of a safe state in an activated technical installation (2),
- and wherein the hard-wired communication interface (18) using control technology comprises a contact-based plug interface (20) on the manual operator-control instrument (9), which plug interface (20) is provided with a first coupling element (21) on the manual operator-control instrument (9) and a second coupling element (22) that can be coupled and decoupled as needed relative to the first coupling element (21), which second coupling element (22) is constructed on the connecting cable (17),
- wherein
- at least one termination indicator (27) is formed on or in the second coupling element (22) directly or in the immediate vicinity of the second coupling element (22) or on the connecting cable 17, which termination indicator (27) can be sensed electronically by a termination-indicator detecting means (28),
- wherein a manual operator-control instrument detecting means (31) is formed, which is provided for sensing of the presence or non-presence of a connection, using control technology, of a manual operator-control instrument (9) to the control system (1),
- and wherein the control system (1), upon sensing of a change from a presence to a non-presence of a connection, using control technology, of a manual operator-control instrument (9) and upon simultaneous sensing of a termination indicator (27) on the corresponding cable (17) to this decoupled manual operator-control instrument (9), recognizes a separation, undertaken intentionally by an operator-control person (11), of the contact-based interface (20) on this manual operator-control instrument (9) and thereupon, as a substitute for the safety switching element (15) that as a consequence has become ineffective on the decoupled manual operator control instrument (9), couples the last valid switched state of the safety switching element (15) in functionally equivalent manner into the safety switching circuit (19), or respectively is designed for bridging the safety switching circuit (19) in the course of unplugging the manual operator-control instrument (9), or is provided for changeover of at least one substitute or parallel contact (34, 34′) to the safety switching element (15) on the manual operator-control instrument (9), inasmuch as the safety switching element (15) on the unplugged manual operator-control instrument (9) has been preset in its non-actuated state or quiescent state immediately before the unplugging of the connecting cable (17) from the manual operator control instrument (9).