Abstract: A magneto-inductive flowmeter having at least one measuring tube for the flow of an electrically conducting medium, having at least one magnetic field generator for generating a preferably alternating magnetic field running at least also perpendicular to the longitudinal axis of the measuring tube, having at least two measuring electrodes—in particular in contact with the medium—and having a functional unit containing at least one evaluation unit and a method of operating same. The magneto-inductive flowmeter is user-friendly in a very particular manner, namely in that the functional unit has a request initiator that can be activated—by the user or the flowmeter itself—, a contacting receiver and an information sender and that by means of the request initiator, a third party can be prompted—by the user or the flowmeter itself—into contact—with the user or with the flowmeter itself.

Abstract: A magnetic-inductive flowmeter and method in which a control circuit and/or evaluation circuit is designed/operated in such a manner that a measuring voltage tapped or tappable by measuring electrodes for flow measurement are evaluated only during a flow measuring time that is less than half the duration of the period of generation of the magnetic field and that the control circuit is designed/operated in such a manner that the measuring electrodes are impinged with conductivity measuring signals only during a conductivity measuring time that lies outside the flow measuring time.

Abstract: A method for operation of several adjacent magnetic-inductive flow meters, each of which has a measurement tube through which an electrically conductive medium flows, a magnetic field generating apparatus for permeating the medium with a magnetic field having a component perpendicular to the longitudinal axis of the measurement tube, and a measurement apparatus for measuring the voltage induced into the medium and for determining the flow rate from the induced voltage. Each flow meter has a control apparatus. In order to prevent variations of mutual influences on the flow rate measurements by the magnetic fields of adjacent flow meters, measured flow rate values from individual measurement processes and synchronous measurement processes are used to determine the mutual influences on the flow rate measurements, and influences that are free of variations are compensated by the magnetic fields of the adjacent flow meters being synchronized.

Abstract: A non-intrinsically safely supplied measurement device (1) with a connecting device (3) having an “increased safety” type of protection for connecting the measurement device (1) to a feed connection (2) in order to supply the measurement device (1) with electricity, an electronic device (4) which contains electronic components of the measurement device (1), a display device (8), a sensor (7) made with “increased safety” or “intrinsic safety” type of protection, and an output circuit (9) that is without at least the “intrinsic safety” type of protection. The electronic device (4) has an “encapsulation” type of protection, the display device (8) has an “intrinsic safety” type of protection and the display device (8), the sensor (7) and the output circuit (9) are connected to the electronic device (4) via connections having an “increased safety” type of protection.

Abstract: A non-intrinsically safely supplied measurement device (1) with a connecting device (3) having an “increased safety” type of protection for connecting the measurement device (1) to a feed connection (2) in order to supply the measurement device (1) with electricity, an electronic device (4) which contains electronic components of the measurement device (1), a display device (8), a sensor (7) made with “increased safety” or “intrinsic safety” type of protection, and an output circuit (9) that is without at least the “intrinsic safety” type of protection. The electronic device (4) has an “encapsulation” type of protection, the display device (8) has an “intrinsic safety” type of protection and the display device (8), the sensor (7) and the output circuit (9) are connected to the electronic device (4) via connections having an “increased safety” type of protection.

Abstract: A magnetoinductive flowmeter and a method for operating same utilizing a measuring tube through which flows an electrically conductive medium, as well as two measuring electrodes and a magnet with two field coils positioned parallel to each other on mutually opposite sides of the measuring tube. The measuring electrodes are so positioned that their connecting line extends along an essentially perpendicular vector relative to the direction of flow and to the magnetic field as well as through the cross-sectional center of the measuring tube. For normal flow-measuring operation, the two field coils are so energized that an essentially homogeneous magnetic field is generated, permeating the medium flowing through the measuring tube, while for determining the flow rate the voltage present between the two measuring electrodes is collected at one or both measuring electrodes and measured against a reference potential.

Abstract: A magnetoinductive flowmeter and a method for operating same utilizing a measuring tube through which flows an electrically conductive medium, as well as two measuring electrodes and a magnet with two field coils positioned parallel to each other on mutually opposite sides of the measuring tube. The measuring electrodes are so positioned that their connecting line extends along an essentially perpendicular vector relative to the direction of flow and to the magnetic field as well as through the cross-sectional center of the measuring tube. For normal flow-measuring operation, the two field coils are so energized that an essentially homogeneous magnetic field is generated, permeating the medium flowing through the measuring tube, while for determining the flow rate the voltage present between the two measuring electrodes is collected at one or both measuring electrodes and measured against a reference potential.

Abstract: The magnetoinductive flowmeter measures the flow volume of a medium traveling through a measuring tube, with a magnet that serves to generate a magnetic field permeating the measuring tube that has a magnetic-field component that extends perpendicular to the direction of flow. The flowmeter also includes a first measuring electrode and a second measuring electrode for collecting a voltage induced in the medium, a reference electrode, as well as a preamplifier to which the potentials collected by the two measuring electrodes are fed. A control circuit element is provided for controlling the common-mode input voltage of the preamplifier and/or the potential span of the dynamic range of the preamplifier in such fashion that the said common-mode input voltage of the preamplifier corresponds to approximately half the maximum output voltage of the preamplifier. This concept also permits the use of preamplifiers that operate with a low supply voltage such as 0/5 V. A measuring method is also disclosed.

Abstract: A method for operating a measuring instrument whose measuring operation is clocked at a measuring frequency. The measured data acquired in the measuring operation are subjected to a frequency analysis and the measuring frequency is automatically controlled as a function of the frequency spectrum thus acquired. In this fashion a good signal-to-noise ratio is obtained.

Abstract: A method for operating a magnetoinductive flowmeter of the type including a measuring tube through which flows an electrically conductive medium, at least two electrodes that are in direct conductive contact with the medium, and at least one magnetic field coil that serves to generate a magnetic field which permeates at least part of the medium and in which a predefined current is impressed between two electrodes that are in wet contact with the flowing medium, the voltage present between the two electrodes or between one of the two electrodes and another electrode that is in wet contact with the flowing medium is measured, and a resistance value is derived from the ratio of the impressed current to the measured voltage. This permits the determination and read-out of the conductivity of the medium flowing through the measuring tube, which constitutes an added benefit for the user of the magnetoinductive flowmeter.

Abstract: A magnetoinductive flowmeter incorporates a magnet for generating a magnetic field that permeates the flowmeter's measuring tube with a magnetic field component perpendicular to the direction of flow, a first electrode and a second electrode which collect a voltage induced in the medium, and an amplifier to which the voltage collected by the electrodes is fed. A test voltage source and a comparator are provided, the test voltage source generating a test voltage, which is applied to the amplifier in a manner whereby the test voltage is superimposed over the voltage collected by the electrodes. The comparator is connected to the amplifier so that the output voltage of the amplifier can be fed to the comparator, and the comparator is designed in a manner whereby the output voltage of the amplifier can be compared with a reference value. This configuration permits easy calibration of the magnetoinductive flowmeter while during operation, any deviation from a calibrated condition can be detected reliably.

Abstract: A magnetoinductive flowmeter incorporates a magnet for generating a magnetic field that permeates the flowmeter's measuring tube with a magnetic field component perpendicular to the direction of flow, a first electrode and a second electrode which collect a voltage induced in the medium, and an amplifier to which the voltage collected by the electrodes is fed. A test voltage source and a comparator are provided, the test voltage source generating a test voltage, which is applied to the amplifier in a manner whereby the test voltage is superimposed over the voltage collected by the electrodes. The comparator is connected to the amplifier so that the output voltage of the amplifier can be fed to the comparator, and the comparator is designed in a manner whereby the output voltage of the amplifier can be compared with a reference value. This configuration permits easy calibration of the magnetoinductive flowmeter while during operation, any deviation from a calibrated condition can be detected reliably.

Abstract: An optoelectronic coupler includes two photodiodes and an optic light guide, where one of the two photodiodes serves as the transmitting diode and the other as the receiving diode and the light guide serves to guide the light emitted by the transmitting diode to the receiving diode. The transmitting diode and the receiving diode are mounted on a circuit board at a distance from each other and the light guide is constituted of a plastic or glass element mounted on the same circuit board. This arrangement provides for a simple optoelectronic coupler design that permits safe operation even from the perspective of explosion protection.

Abstract: The magnetoinductive flowmeter measures the flow volume of a medium traveling through a measuring tube, with a magnet that serves to generate a magnetic field permeating the measuring tube that has a magnetic-field component that extends perpendicular to the direction of flow. The flowmeter also includes a first measuring electrode and a second measuring electrode for collecting a voltage induced in the medium, a reference electrode, as well as a preamplifier to which the potentials collected by the two measuring electrodes are fed. A control circuit element is provided for controlling the common-mode input voltage of the preamplifier and/or the potential span of the dynamic range of the preamplifier in such fashion that the said common-mode input voltage of the preamplifier corresponds to approximately half the maximum output voltage of the preamplifier. This concept also permits the use of preamplifiers that operate with a low supply voltage such as 0/5 V. A measuring method is also disclosed.

Abstract: A method for operating a magnetoinductive flowmeter of the type including a measuring tube through which flows an electrically conductive medium, at least two electrodes that are in direct conductive contact with the medium, and at least one magnetic field coil that serves to generate a magnetic field which permeates at least part of the medium and in which a predefined current is impressed between two electrodes that are in wet contact with the flowing medium, the voltage present between the two electrodes or between one of the two electrodes and another electrode that is in wet contact with the flowing medium is measured, and a resistance value is derived from the ratio of the impressed current to the measured voltage. This permits the determination and read-out of the conductivity of the medium flowing through the measuring tube, which constitutes an added benefit for the user of the magnetoinductive flowmeter.

Abstract: An optoelectronic coupler includes two photodiodes and an optic light guide, where one of the two photodiodes serves as the transmitting diode and the other as the receiving diode and the light guide serves to guide the light emitted by the transmitting diode to the receiving diode. The transmitting diode and the receiving diode are mounted on a circuit board at a distance from each other and the light guide is constituted of a plastic or glass element mounted on the same circuit board. This arrangement provides for a simple optoelectronic coupler design that permits safe operation even from the perspective of explosion protection.

Abstract: A magnetoinductive flowmeter for moving fluids, incorporating a sensor unit and a processing and power supply unit, the sensor unit encompassing a measuring tube, field coils which serve to generate a periodically alternating magnetic field in a direction at least essentially perpendicular to the axis of the measuring tube, and two measuring electrodes positioned along a line that extends at least essentially in a direction perpendicular to the axis of the measuring tube and perpendicular to the vector of the magnetic field, with field-coil feed lines connecting the field coils of the sensor unit to the processing and power supply unit. The sensor unit encompasses a sensor-data memory module in which specific parameters of the sensor unit are stored and from which the stored specific parameters can be transferred to the processing and power supply unit. This permits the simple adaptation of an existing sensor unit to a new processing power supply unit or vice versa.

Abstract: A magnetically inductive flowmeter for flowing media, with a measuring tube, with a magnet for generating a magnetic field passing essentially perpendicular to the axis of the measuring tube and to the direction of the magnetic field, with at least two measuring electrodes arranged along a connecting line passing essentially perpendicular to the axis of the measuring tube and to the direction of the magnetic field, with a reference electrode and with a difference amplifier having a reference potential connection connected with the measuring electrodes via measuring electrode connections and serving for amplification of the measuring voltage present on the measuring electrodes.

Abstract: The circuit arrangement for measured value detection, transfer and analysis, with a measured value detection section (1), a measured value analyzing section (2) and a connection (5) consisting only of an outgoing conductor (3) and a return conductor (4) between the measured value detection section (1) and the measured value analyzing section (2), in connection with which the measured value detection section (1) has a measured value recorder (6), a measuring transformer circuit (7), a switch controller (8) connected upstream from the measuring transformer circuit (7) and a current regulator (9) connected upstream from the switch controller (8), in connection with which the measured value analyzing section (2) has a voltage source (10) and an analyzing circuit (11), and the switch controller (8) delivers a constant operating voltage for the measuring transformer circuit (7), and the current regulator (9)—controlled by the measuring transformer circuit (7)—sets a measured value and power supply curre

Abstract: A magnetoinductive flowmeter for moving fluids, incorporating a sensor unit and a processing and power supply unit, the sensor unit encompassing a measuring tube, field coils which serve to generate a periodically alternating magnetic field in a direction at least essentially perpendicular to the axis of the measuring tube, and two measuring electrodes positioned along a line that extends at least essentially in a direction perpendicular to the axis of the measuring tube and perpendicular to the vector of the magnetic field, with field-coil feed lines connecting the field coils of the sensor unit to the processing and power supply unit. The sensor unit encompasses a sensor-data memory module in which specific parameters of the sensor unit are stored and from which the stored specific parameters can be transferred to the processing and power supply unit. This permits the simple adaptation of an existing sensor unit to a new processing power supply unit or vice versa.