Abstract: A signaling device for a safety circuit has an input part for receiving an external state variable, at least one switching element and a control part. The control part controls the at least one switching element as a function of the external state variable, such that a signal applied to the input is communicated to the output. According to one aspect of the invention, the input of the switching element is internally connected to a fixed potential, preferably a fixed High potential. In a safety circuit for turning off a hazardous installation, such signaling devices are connected in series with one another to a safety controller. In such an arrangement, the control part of the downstream second signaling device also controls its switching elements as a function of the output of the first signaling device.

Abstract: A safety switching apparatus for failsafe disconnection of an electrical load has a first and a second connecting terminal for connecting a first signaling switch and a third and a fourth connecting terminal for connecting a second signaling switch. It also has a first and a second output switching element, which are designed to produce a redundant output switching signal. The first connecting terminal is connected to a first potential and the third connecting terminal is connected to a second potential. The potentials differ from one another. In addition, the second connecting terminal is coupled to the first switching element in such a way that the first switching element receives the first potential via the first signaling switch. Likewise, the fourth connecting terminal is coupled to the second switching element in such a way that the second switching element receives the second potential via the second signaling switch.

Abstract: A safety switching device comprises a position encoder, such as a potentiometer, for user selection of an operational quantity, such as an operating mode. The position encoder has a first terminal, a second terminal, and a tap moveable through a plurality of positions. A total impedance is defined between the first terminal and the second terminal. A first partial impedance is defined between the first terminal and the tap, and a second partial impedance is defined between the tap and the second terminal. An arrangement for determining an instantaneous position of the tap comprises a first evaluation circuit designed to determine a first measurement value representative of the first partial impedance, and a second evaluation circuit designed to determine a second measurement value representative of the second partial impedance. At least one from the first and second evaluation circuits is designed to determine the instantaneous position of the tap by means of the first and second measurement values.

Abstract: The invention relates to a safety switching device for the failsafe shutdown of an electric load, such as an electrically driven machine. The safety switching device has a signal processing part for receiving and evaluating an input-side switching signal, which, for example, originates from an emergency stop switch. It also has at least one switching element which, controlled by the signal processing part, provides an output-side switching signal for shutting down the load. An anti-surge element is provided for canceling reaction voltage spikes when the load is shut down. The anti-surge element has at least a first and a second anti-surge operating mode, which can be activated as an alternative to one another.

Abstract: A safety switching apparatus for failsafe disconnection of an electrical load has a first and a second connecting terminal for connecting a first signaling switch and a third and a fourth connecting terminal for connecting a second signaling switch. It also has a first and a second output switching element, which are designed to produce a redundant output switching signal. The first connecting terminal is connected to a first potential and the third connecting terminal is connected to a second potential. The potentials differ from one another. In addition, the second connecting terminal is coupled to the first switching element in such a way that the first switching element receives the first potential via the first signaling switch. Likewise, the fourth connecting terminal is coupled to the second switching element in such a way that the second switching element receives the second potential via the second signaling switch.

Abstract: A safety switching device comprises a position encoder, such as a potentiometer, for user selection of an operational quantity, such as an operating mode. The position encoder has a first terminal, a second terminal, and a tap moveable through a plurality of positions. A total impedance is defined between the first terminal and the second terminal. A first partial impedance is defined between the first terminal and the tap, and a second partial impedance is defined between the tap and the second terminal. An arrangement for determining an instantaneous position of the tap comprises a first evaluation circuit designed to determine a first measurement value representative of the first partial impedance, and a second evaluation circuit designed to determine a second measurement value representative of the second partial impedance. At least one from the first and second evaluation circuits is designed to determine the instantaneous position of the tap by means of the first and second measurement values.

Abstract: A signaling device for a safety circuit has an input part for receiving an external state variable, at least one switching element and a control part. The control part controls the at least one switching element as a function of the external state variable, such that a signal applied to the input is communicated to the output. According to one aspect of the invention, the input of the switching element is internally connected to a fixed potential, preferably a fixed High potential. In a safety circuit for turning off a hazardous installation, such signaling devices are connected in series with one another to a safety controller. In such an arrangement, the control part of the downstream second signaling device also controls its switching elements as a function of the output of the first signaling device.

Abstract: An apparatus for evaluating the fetal condition prior to or under birth receives the signals of a fetal heart rate transducer and a toco transducer. The signals are first preprocessed in the time domain and in the frequency domain. A trace processor identifies possible events like decelerations and contractions. These are validated by a validation processor, whose output is then classified by a classification processor. A score processor scores the events and cooperates with an alarm handler and a reasoning processor. The rules according to which these processors operate are stored in a rule memory and may be edited or selected, or new rules may be set up, by a display or personal computer under control of an expert interface.