Abstract: A circuit configuration for monitoring and/or for regulating supply voltages. The circuit enables at least two supply voltages (U12) or (U22) that are produced by means of two feed-ins (Q1, Q2) and that are provided for consumer circuits (V1, V2) to be monitored and limited simultaneously. To this end, the circuit configuration comprises a corresponding voltage monitoring electronics unit which detects the supply voltages (U12, U22) and compares them with associated tolerance values (?U12, ?U22). The voltage monitoring electronics unit also provides a control signal (y) which signals whether the first supply voltage (U12) is lower than the associated tolerance value (?U12). The control signal (y) is used to control a shunt electronics unit through which a shunt current (IS) passes temporarily.

Abstract: The invention concerns a device for measuring and/or monitoring a process parameter, with a sensor, an intermittently working measurement circuit, which has at least one energy storer unit, wherein the measurement circuit or individual components of the measurement circuit are activated for a predetermined time span, the so-called active phase, and with a control center, wherein the measurement circuit and the control center are connected with one another over a two-wire line and wherein a control-/evaluation-unit is provided, which activates the measurement circuit at the earliest, when the energy in the energy storer unit has reached a predetermined level.

Abstract: The invention concerns a device (1) for measuring and/or monitoring a process parameter, with a sensor (2), an intermittently working measurement circuit (3), which has at least one energy storer unit (16), wherein the measurement circuit (3) or individual components of the measurement circuit (3) are activated for a predetermined time span, the so-called active phase, and with a control center (14), wherein the measurement circuit (3) and the control center (14) are connected with one another over a two-wire line (12, 13) and wherein a control-/evaluation-unit (4) is provided, which activates the measurement circuit (3) at the earliest, when the energy in the energy storer unit (16) has reached a predetermined level.

Abstract: The invention relates to a circuit configuration for monitoring and/or for regulating supply voltages. Said circuit enables at least two supply voltages (U12) or (U22) that are produced by means of two feed-ins (Q1, Q2) and that are provided for consumer circuits (V1, V2) to be monitored and limited simultaneously. To this end, the circuit configuration comprises a corresponding voltage monitoring electronics unit (1) which detects the supply voltages (U12, U22) and compares them with associated tolerance values (&Dgr;U12, &Dgr;U22). The voltage monitoring electronics unit (1) also provides a control signal (y) which signals whether the first supply voltage (U12) is lower than the associated tolerance value (&Dgr;U12). The control signal (y) is used to control a shunt electronics unit (2) through which a shunt current (IS) passes temporarily.

Abstract: An apparatus for determining a physical process variable of a medium (2) which can be used in conjunction with various sensor types, the sensors having in common that they determine a process variable by means of a delay-time method. The apparatus has a sensor (4), a sensor-specific application unit (5) and an evaluation unit (6), which is essentially independent of the sensor type used, the sensor (4) being assigned a transmitting/receiving unit (7), the transmitting unit (7a) transmitting measuring signals in the direction of the medium (2) and the receiving unit (7b) receiving the measuring signals influenced by the interaction with the medium (2), and the application unit (5) being designed in such a way that it provides measurement data, independently of the type of sensor (4) used, from which the evaluation unit (6) determines the physical process variable using a delay-time method by means of a uniform evaluation algorithm.

Abstract: The transducer supply is configured for supplying a passive transducer arranged in an explosion-hazard zone with electrical energy from a DC voltage source. The electrical energy is transmitted via a two-wire connection, via which in the opposite direction the measured value sensed by the transducer is transmitted by the transducer setting the direct current obtained from the DC voltage source to a value variable between two limit values. As a means of protection a transformer is inserted in the two-wire connection which affects DC decoupling. The direct current is chopped in accordance with the principle of a DC voltage converter at the primary side of the transformer and re-rectified on the secondary side.

Abstract: A level measuring device suitable for highly accurate measurements. A transmission pulse generator generates microwave pulses at a transmission repetition rate and transmits them through an antenna towards a material whose level is to be measured. Echo signal from the surface of the material are received by the antenna. A reference pulse generator generates reference pulses similar to the transmission pulses but at a reference repetition rate which differs from the transmission repetition rate by a small frequency difference. The echo signal and reference pulse are input to a first mixer which generates an intermediate frequency signal that, with respect to the echo signal, is slowed by a time dilation factor equal to the quotient of the transmission repetition rate and the frequency difference. A first subcircuit samples the intermediate frequency signal, the time interval between two successive samplings equaling a time unit.

Abstract: The electronic switching device serves to control the connection of a load to a voltage source by a switch which is controlled in a first operating mode directly by a binary signal furnished by a signal processing circuit and in a second operating mode inverted. The switching device has three terminals, of which the first permanently remains connected to a first terminal of the voltage source and to a first terminal of the load, whilst of the other two switching device terminals the one is connected to the second terminal of the voltage source and the other to the second terminal of the load. The switching device is configured so that it can be changed over from the one operating mode into the other by interchanging the connections between these two other switching device terminals and the second terminals of the voltage source and of the load, respectively.

Abstract: The determination and/or monitoring of a predetermined material level in a container is effected with the help of a material level sensor which contains a mechanical oscillatory structure, an electromechanical excitation transducer and two electromechanical reception transducers. The mechanical oscillatory structure is secured at the height of the predetermined material level in such a way that it comes into contact with the material when said material reaches the predetermined material level. Each reception transducer is connected to the input of an assigned circuit channel, which contains an amplifier circuit, the output of which is connected to the excitation transducer and which is so constructed that the mechanical oscillatory structure is excited to produce oscillations with its natural resonance frequency. The two circuit channels are activated alternately by means of a control circuit.