Abstract: A field device electronics for a conductive, limit-level switch, with a conductive probe and a measuring circuit including a control/evaluation circuit. The measuring circuit, a measuring bridge circuit is present, with at least one coupling capacitor (C2) being present for the DC voltage separation of the probe from the measuring circuit, and with the at least one coupling capacitor (C2) being integrated into the measuring bridge circuit.

Abstract: A field device electronics for a conductive, limit-level switch, with a conductive probe and a measuring circuit including a control/evaluation circuit. The measuring circuit, a measuring bridge circuit is present, with at least one coupling capacitor (C2) being present for the DC voltage separation of the probe from the measuring circuit, and with the at least one coupling capacitor (C2) being integrated into the measuring bridge circuit.

Abstract: A field device electronics with a sensor unit for capacitive fill level measurements in a container, wherein the field device electronics is connected over appropriate signal paths with the sensor unit, wherein the field device electronics produces a voltage signal for driving the sensor unit and receives and evaluates a measurement current from the sensor unit. According to the invention, an analog/digital converter digitizing the analog measurement current, a microprocessor and a memory unit are present, wherein the microprocessor utilizes predetermined program routines to perform the production of the voltage signal and the evaluation of the measurement current and a compensation of interference parameters and a determination of the parameters of the sensor-container arrangement which are to be determined, with the associated programs being stored in the memory unit.

Abstract: In a method for the capacitive fill level measurement of a fill substance in a container, electrical current is determined at two alternating voltage signals U1, U2 of differing frequencies f1, f2. On the basis of the two values for current, the capacitive reactance and therewith the fill height h of the fill substance can be easily determined. Influences of ohmic resistance on the measurement results are eliminated in this method.

Abstract: A field device electronics with a sensor unit for capacitive fill level measurements in a container, wherein the field device electronics is connected over appropriate signal paths with the sensor unit, wherein the field device electronics produces a voltage signal for driving the sensor unit and receives and evaluates a measurement current from the sensor unit. According to the invention, an analog/digital converter digitizing the analog measurement current, a microprocessor and a memory unit are present, wherein the microprocessor utilizes predetermined program routines to perform the production of the voltage signal and the evaluation of the measurement current and a compensation of interference parameters and a determination of the parameters of the sensor-container arrangement which are to be determined, with the associated programs being stored in the memory unit.

Abstract: In a method for the capacitive fill level measurement of a fill substance in a container, electrical current is determined at two alternating voltage signals U1, U2 of differing frequencies f1, f2. On the basis of the two values for current, the capacitive reactance and therewith the fill height h of the fill substance can be easily determined. Influences of ohmic resistance on the measurement results are eliminated in this method.

Abstract: A device for transmitting data between a sensor, in particular a capacitive level sensor, and an analyser unit, whereby the sensor and the analyser unit are physically separate from each other and a method for operating said device. The device and method permit the testing and/or adjusting and/or operation of a sensor, which is active. A first processor unit is dedicated to the sensor and a second processor unit is dedicated to the evaluating unit. Connecting lines are provided, by means of which both processor units exchange bi-directional data.

Abstract: The invention relates to a device for determining the level (F) of a medium (3) in a container (2) using a capacitive sensor (4). A voltage source which subjects the sensor (4) to a measuring frequency (fM) is provided, as is a measuring/evaluating circuit (6) which establishes the measured capacitance (CM), compares this to a predetermined capacitance value and provides the information concerning the level (F) of the medium (3) in the container (2). The aim of the invention is to increase the measuring sensitivity of a capacitive sensor (4) without increasing the sensitivity of the sensor to interfering signals. To this end, the measuring/evaluating circuit (6) has at least one inductance (L) which together with the measured capacitance (CM), forms a resonant circuit (7).

Abstract: The invention relates to a device for determining the level (F) of a medium (3) in a container (2) using a capacitive sensor (4). A voltage source which subjects the sensor (4) to a measuring frequency (fM) is provided, as is a measuring/evaluating circuit (6) which establishes the measured capacitance (CM), compares this to a predetermined capacitance value and provides the information concerning the level (F) of the medium (3) in the container (2). The aim of the invention is to increase the measuring sensitivity of a capacitive sensor (4) without increasing the sensitivity of the sensor to interfering signals. To this end, the measuring/evaluating circuit (6) has at least one inductance (L) which together with the measured capacitance (CM), forms a resonant circuit (7).

Abstract: The invention relates to a universal process adapter (10) having a housing (112), a probe in the form of a rod or cable, and a standardized attachment apparatus (130), by means of which the process adapter can have any desired further housing (212) added to it.

Abstract: A voltage regulator circuit for generating a regulated output DC voltage from a non-regulated DC or AC voltage, comprises an input rectifier circuit for rectifying the non-regulated AC voltage and a series regulator, containing a gate-controllable transistor, which regulates the output voltage supplied to it by the rectifier to a first voltage value. The transistor of the series regulator is a field-effect transistor (20) which in the ON condition charges a charging capacitor (46), the charging voltage of which forms the regulated output voltage. Connected to the gate terminal (21) of the field-effect transistor is a first threshold circuit (26, 28, 30, 32) receiving the non-regulated DC voltage which applies to this gate terminal (21) a voltage turning OFF the field-effect transistor (20) as soon as the non-regulated DC voltage exceeds a predetermined threshold value.