Abstract: An apparatus performs braking power monitoring and safety-related locking of a drive of a technical system. The technical system has two machine parts that are movable relative to one another and that are moved towards one another by the drive at a defined actuation interval. A first controller has an input for receiving an encoder signal from an encoder coupled to a drive shaft of the drive. The first controller has an output for outputting an error signal. The first controller determines a value for an acceleration from the encoder signal when a brake coupled to the drive shaft acts with its greatest possible braking force on the drive shaft of the drive and locks the drive in a safety-related manner when the determined value exceeds a limit value stored in the first controller.

Abstract: The present invention relates to a circuit arrangement for safe disconnection of an installation, in particular a machine installation. The arrangement comprises a signaling device which produces a defined output signal depending on an operating condition of the installation. Furthermore, it comprises a safety switching device which disconnects the installation in a fail-safe manner depending on the defined output signal. The defined output signal comprises a steady-state signal level over a period of time during operation of the installation. According to one aspect of the invention, the safety switching device comprises a clock generator for generating a clock signal, and an input stage which modulates the output signal from the signaling device with the clock signal.