Endress + Hauser Flowtec Ag

Rémy Scherrer

Robert Lalla

Alfred Rieder

Hao Zhu

Martin Josef Anklin

Johan Pohl

Reinhard Huber

A method for operating a measuring device with a measuring sensor having an oscillator, the oscillator having a vibratory measuring tube for guiding a medium, comprises: Determining a current value of a resonance frequency for a vibration mode of the oscillator; exciting a vibration out of resonance with an excitation frequency that differs from the current value of the resonance frequency; and determining the amplitude of a sensor signal that represents the vibration out of resonance. The amplitude of the sensor signal of the vibration out of resonance, a sensor signal of a vibration sensor of the oscillator, is determined by a low-pass filter the time constant of which is not less than 1000 period lengths of the vibration out of resonance. Also disclosed is a measuring device for carrying out said method.

Method for operating a measuring device with at least one oscillator, and measuring device for carrying out said method

A Coriolis mass flow meter comprises a transformer circuit configured to receive and analyze vibration measurement signals to determine mass flow measurement values which represent a mass flow of a fluid and to determine characteristic number values for at least one sensor characteristic number, which characterizes and/or is based on at least one harmonic component of at least one of the vibration measurement signals, wherein each vibration measurement signal includes a useful component, having a frequency corresponding to a drive frequency with an amplitude based on a respective magnetic flux through a respective vibration sensor of the flow meter, and a harmonic component having a frequency corresponding to a whole-number multiple of the drive frequency and an amplitude based on the respective magnetic flux.

Coriolis mass flow meter

Disclosed is a measurement pickup for determining the mass flow rate of a liquid comprising: at least one measurement tube for carrying the liquid having an inlet-side end section and an outlet-side end section; a support body on which the measurement tube is mounted an exciter for exciting vibrations of the measurement tube; at least one vibration sensor for detecting vibrations of the measurement tube; an operating and evaluation circuit for driving the exciter, for receiving the signals of the vibration sensor, and for ascertaining a measured value representing the mass flow rate. The operating and evaluation circuit comprises an adaptive low-pass filter for filtering the sequence of measured values representing the mass flow rate, wherein the low-pass filter has at least one filter parameter dependent on at least one adaptive controlled variable that, for its part, is dependent on the gas content of the test medium.

Measurement pickup for determining the mass flow rate of a liquid

The Coriolis mass flowmeter includes a measuring tube, an exciter mechanism, a sensor arrangement, and an electronic transmitter circuit including measuring and control electronics and drive electronics connected to the measuring and control electronics. The drive electronics are adapted, in a first operating mode, to generate an electrical driver signal that supplies electrical power to the exciter mechanism such that the measuring tube executes forced oscillations having an excitation frequency and, in a second operating mode, to cease generating the electrical driver signal. The transmitter circuit is adapted to switch the drive electronics from the first operating mode to the second operating mode such that the measuring tube executes free, damped oscillations in the second operating mode, and the measuring and control electronics are adapted to, based on a phase difference between oscillation measuring signals from the sensor arrangement, to generate measured values representing the mass flow rate.

Coriolis mass flowmeter

A method for monitoring oscillation characteristics in a Coriolis, flow measuring device and to a correspondingly formed, Coriolis, flow measuring device in the case of which an excited oscillatory system is simulated with a digital model, which has at least one fittable parameter. The simulating includes, in such case, excitating the digital model in the same manner as the oscillatory system, calculating a simulation response variable of the simulated oscillations according to the digital model, and, performed over a plurality of signal modulations, iterative conforming of the at least one, fittable parameter in such a manner that the simulation response variable interatively approaches the response variable. Furthermore, it is ascertained whether a corresponding limit value is exceeded by the at least one, interatively ascertained parameter value for the at least one, fittable parameter or by at least one variable derived from the at least one, iteratively ascertained parameter value.

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Oberdorf, France

Rémy Scherrer