A method for determining a liquid portion of a flowing medium with a nuclear magnetic flowmeter includes: generating a gradient magnetic field in a measuring tube volume of the flowmeter; exposing the medium to the gradient magnetic field and a magnetic field generated by a magnetizing device of the flowmeter; generating and irradiating an excitation signal into the magnetized medium for exciting nuclear magnetic resonances therein; measuring nuclear magnetic resonances excited by the excitation signal in the magnetized medium as a measuring signal; determining frequencies of the nuclear magnetic resonances in the measuring signal; assigning the determined frequencies to positions along a first gradient direction in the measuring tube volume; assigning the nuclear magnetic resonances at the positions to liquid and gaseous portions of the medium; and determining a liquid portion of the medium in the measuring tube volume from the positions of the nuclear magnetic resonances.

The present invention relates to a flow sensor for measuring a flow difference having at least two measurement chambers through which fluid is conductible; at least one means for producing a magnetic field for charge separation in a fluid flowing through the at least two measurement chambers; and at least one means for measuring an electric potential in the fluid flowing through the at least two measurement chambers, with the at least two measurement chambers being arranged such that they are run through by the same magnetic field line of the magnetic field for charge separation.

A flowmeter for gaseous fluid includes a conduit composed of non-electrically conductive material for passage of an ionized flow of the gaseous fluid therethrough. The flowmeter further includes an electromagnetic sensor arranged to measure a magnetic field generated about the conduit by the passage of the ionized flow and generate a signal proportional to the magnetic field.

The invention relates to a magnetic-inductive flowmeter for measuring the flow of a flowing, conductive medium. The flowmeter has a measuring tube, a magnetic field generating device, two pin shaped measuring electrodes, insertion parts each having a through-hole through which the two measuring electrodes respectively extend, the measuring electrodes have at least in sections a non-circular cross section and the through-holes of the two insertion parts have a contour complementary thereto. The pin shaped measuring electrodes are at least partially provided with an external, thread and a nut is respectively screwed thereon, by means of which the measuring electrodes and the associated insertion parts are respectively firmly connected to the measuring tube.

A magnetically inductive flowmeter includes a measuring tube having a tube axis and a tube wall; a magnet system for producing a magnetic field that extends perpendicularly to the tube axis; at least one pair of measuring electrodes for sensing an electrical voltage induced in the medium by the magnetic field; and an electronic measuring/operating circuit for operating the magnet system and the measuring electrodes. The magnet system includes a coil system having a coil having a coil core and further includes two pole shoes. The coil system includes a field guide-back, wherein a tangential fraction of the magnetic field in the coil relative to the measuring tube axis amounts to at least 90% of the total magnetic field. The field guide-back has a guide-back part that extends through the coil and forms the coil core of the coil.

Disclosed is a device for measuring fill level of a liquid comprising: a measuring tube having a tube wall extending between first and second terminal openings and which surrounds a volume for guiding the liquid, wherein a tube axis extends between the two tube openings; a first conductor extending at least sectionally around the volume and is electrically insulated from the volume; a second conductor extending at least sectionally around the volume and is electrically insulated from the first conductor and from the volume, wherein the two conductors extend essentially in parallel with one another and form a waveguide for microwaves; an HF circuit for in-coupling a microwave signal into the waveguide and for receiving reflected microwave signals out-coupled from the waveguide; an operating and evaluating circuit for determining fill level of the liquid in the measuring tube based on received microwave signals.

A magnetic-inductive flowmeter includes a tube, electrodes in contact with a medium in the tube, a magnetic field generator, an impedance signal generator, and a control device. A first signal path interconnects the impedance signal generator and a first electrode, and a second signal path interconnects the impedance signal generator and a second electrode. A first switch and first and third capacitors are connected such that, in a first state, only the first capacitor and, in a second state, only the third capacitor is in the first signal path. A second switch and second and fourth capacitors are connected such that, in a first state, only the second capacitor and, in a second state, only the fourth capacitor is in the second signal path. The control device sets the switches to the first state during a positive magnetic phase and to the second state during a negative magnetic phase.

The present disclosure relates to a magnetic-inductive flowmeter for measuring flow velocity of a medium, comprising a measuring tube; an apparatus positioned toward a cross-section of the measuring tube for producing a magnetic field extending perpendicular to a longitudinal direction, wherein the apparatus includes a segment coupling the magnetic field into the medium, wherein the segment surrounds the measuring tube over a first angle; and an electrode system having at least two electrode pairs adapted to register a voltage induced in the medium, wherein a second angle defines a minimum circular sector in which the electrodes located on one side of the measuring tube are distributed, wherein first and second angles are so matched to one another that the flowmeter is insensitive to departures from a rotationally symmetric flow such that the flowmeter in a test measurement has a measurement error of flow velocity less than 1.0%.

The present disclosure relates to a magnetic-inductive flowmeter for measuring flow velocity of a medium, comprising a measuring tube; an apparatus positioned toward a cross-section of the measuring tube for producing a magnetic field extending perpendicular to a longitudinal direction, wherein the apparatus includes a segment coupling the magnetic field into the medium, wherein the segment surrounds the measuring tube over a first angle; and an electrode system having at least two electrode pairs adapted to register a voltage induced in the medium, wherein a second angle defines a minimum circular sector in which the electrodes located on one side of the measuring tube are distributed, wherein first and second angles are so matched to one another that the flowmeter is insensitive to departures from a rotationally symmetric flow such that the flowmeter in a test measurement has a measurement error of flow velocity less than 1.0%.

A method for operating a measuring system includes: carrying out impedance measurements with at least three property measurement electrodes on a medium in a first region of a measuring tube interior over an impedance measurement period and, at the same time, signaling the impedance measurement period by a measuring signal to a flow measurement controller; determining a property of the medium from the impedance measurements using impedance tomography; generating a magnetic field in the medium in a second region of the measuring tube interior by the flow measurement controller using a magnetic field generator; carrying out voltage measurements at a sampling rate using at least two flow measurement electrodes on the medium in the second region; taking an impedance measurement duration from the measuring signal; and discarding the voltage measurements carried out during the impedance measurements; and determining a flow rate of the medium from the remaining voltage measurements.