A flow tube liner for a flow tube assembly of a magnetic flowmeter includes a cylindrical wall. The cylindrical wall includes an electrically insulative interior layer and a metallic exterior layer. The exterior layer is bonded to an exterior surface of the interior layer.

An example system is configured for determining properties of a fluid in a conduit. The system includes a mass flow meter including a hollow conduit having an inlet, an outlet, and a wall. The conduit is for conducting the fluid. The system includes a driver coupled to the conduit. The driver is configured for inducing an oscillation in the conduit. The system includes two or more accelerometers coupled to the conduit. The two or more accelerometers are configured for measuring displacement of the conduit. The system includes an electrical permittivity sensor coupled to the conduit. The electrical permittivity sensor is configured for measuring electrical permittivity of the fluid.

A magnetic flowmeter for measuring a fluid flow includes a flow tube assembly receiving the flow and having a coil with first and second coil wires for receiving a coil current and responsively producing a magnetic field thereby generating an EMF in the fluid representative of a flow rate. An EMF sensor is arranged to sense the EMF and generate an output indicating the flow rate. Current supply circuitry applies a current supply signal to the coil. A load leveling boost supply provides power to the current supply circuitry. In another aspect, power scavenging circuitry recovers power from the coil.

The present disclosure relates to a method for producing a coil holder of a magnetic inductive flowmeter by injection molding, wherein the coil holder has two coil cores cast in a plastic casting, which two coil cores each have a first longitudinal axis, the method comprising: providing and positioning of a mold with a cast volume and the two coil cores, wherein each coil core has two end faces and a lateral surface, wherein the lateral surface has a central region and two outer regions bounding the central region, wherein the cast volume completely bounds the central regions in a coil region, wherein the outer regions and the end faces are outside of the cast volume; filling the cast volume with a plastic; allowing the plastic to harden; and removing the mold from the plastic casting, wherein the cast volume is continuous.

A flowmeter includes a control and evaluation unit, a sensor unit for capturing a primary variable, and a memory for storing data sets. The control and evaluation unit has a computing unit for determining the flow rate and/or for operating the sensor unit. The sensor unit is connected to the computing unit. During operation, the computing unit determines the flow rate from the primary variable, and determines the flow rate based on a data set and/or controls the sensor unit based on a data set. The data set includes a set of calibration values and/or a parameter for the operation of the sensor unit, and/or a parameter for determining the flow rate. The data set is assigned to a value of a state variable. The state variable is a medium parameter and/or a process parameter. The computing unit exchanges the data set depending on a change in the state variable.

A magnetic-inductive flowmeter and a method for operating the flowmeter are disclosed. The flowmeter has a measuring tube, a magnetic field generator, and a controller with first and second measuring terminals. A medium is made to flow through the measuring tube. The controller performs the following steps: generating and feeding an emission signal and receiving a receive signal caused by the emission signal at the first measuring terminal and second measuring terminal; determining an impedance with an impedance amount and an impedance phase using the emission signal and the receive signal; and signaling a short circuit if the impedance amount is smaller than a first limit impedance amount and the impedance phase is larger than a limit impedance phase.

A magnetic flowmeter includes a flow tube assembly, an electromotive force (EMF) sensor, a power amplifier, a current sampling circuit, and a controller. The flow tube assembly receives the fluid flow, and includes a coil configured to receive a coil current and induce an EMF in the fluid flow that is proportional to the flow rate. The EMF sensor generates an output indicating the induced EMF. The power amplifier is configured to generate unfiltered current pulses at a first frequency. The power amplifier includes a low pass filter that attenuates the unfiltered current pulses to form coil current pulses at a second frequency that form the coil current. The current sampling circuit samples the coil current pulses at a sampling frequency. The controller is configured to change a relationship between the sampling frequency and the first frequency, and adjust the coil current based on the samples.

An Electromagnetic (EM) flowmeter includes pair of coils powered by currents for generating electromagnetic fields, and pair of electrodes for measuring electromotive forces generated by interaction of electromagnetic and flow fields in fluid. To improve measurements during flow distortion, a system configures current in the pair of coils based on a relation between a distance of the EM flowmeter from flow distorting features in the flow pipe and the characteristic length of the EM flowmeter. Further, based on configuration of current in the pair of coils, signals are generated due to electromotive forces and are measured to estimate flow in the pipe.

Disclosed is a magnetically inductive flow measuring probe for determining flow rate and/or flow velocity of a medium, which includes a front part with a front end having a center, a housing, a magnetic field producing means arranged in the housing for producing a magnetic field passing through the front end, and a measuring- and evaluation unit, and characterized in that there are arranged on the front end and forming galvanic contact with the medium three measuring electrodes, which form three measuring electrode pairs, and in that the measuring- and evaluation unit is adapted to register induced measured voltages between at least two measuring electrode pairs, especially three measuring electrode pairs, and to ascertain flow rate and/or flow velocity of the medium as a function of the registered voltages.

The disclosure relates to a magnetoinductive flowmeter. In order to detect gas bubbles in a measuring tube, and thus an incompletely filled measuring tube, the control signal with which the magnetic field generating device is actuated is designed as an alternating rectangular pulse with time delays. A first pulse time delay is provided after a positive rectangular pulse and a second pulse time delay is provided after a negative rectangular pulse during one period, wherein no magnetic fields are provided during the pulse time delays. The measurement signal is evaluated during the duration of the rectangular pulses (MB+, MB−) in order to ascertain the flow speed of the medium and during the duration of the time delays (Mess1 , Mess2) in order to monitor the functionality, wherein the impedence between the two measurement electrodes is ascertained via the noise level of the measurement signal during the time delays (Mess1 , Mess2), and the noise level of the measurement signal during the time delays (Mess1 , Mess2) is a measurement of a malfunction, the impedance between the two measurement electrodes being influenced by air bubbles or foreign particles in the measurement medium.