The modification method for the gas density relay, the gas density relay with the online self-check function and the check method thereof provided by this application are used for high-voltage and medium-voltage electrical equipment, including a gas density relay body, a gas density detection sensor, a temperature regulating mechanism, an online check contact signal sampling unit and an intelligent control unit. Regulate temperature rise and fall of the temperature compensation element of the gas density relay body through the temperature regulating mechanism, which leads to a contact action of the gas density relay body, the contact action is transferred to the intelligent control unit through the online check contact signal sampling unit, and the intelligent control unit detects the operating value and/or return value of the contact signal of the gas density relay body based on the density value at the time of contact action. The gas density relay check can be completed without maintainer at the site, so as to realize free maintenance, greatly improve the reliability of power grid, increase work efficiency and reduce the cost.

A device for determining and/or monitoring at least one process variable of a medium includes a mechanically vibratable unit, a drive/receiver unit and an electronic unit. The drive/receiver unit is designed to excite the mechanically vibratable unit to produce mechanical vibrations using an electrical excitation signal, and to receive the mechanical vibrations of the mechanically vibratable unit and convert them into an electrical reception signal. The electronics unit is designed to generate the excitation signal on the basis of the received signal, to set a frequency of the excitation signal in such a way that there is a predeterminable phase shift between the excitation signal and the received signal, and to determine the at least one process variable on the basis of the received signal, the mechanically vibratable unit comprising a diaphragm, and a surface of the diaphragm facing the process being curved.

A fluid sensor includes a tuning fork mechanical resonator including a base and a tine projecting from the base along a longitudinal direction of the tine, and a pair of electrodes disposed on the tine. The base and the tine are formed from a piezoelectric material including lithium tantalate. The electrodes are exposed to a fluid.

A digital densitometer for a fluid gauging system includes a frequency detection device configured to be disposed within a fluid tank, wherein a frequency detected by the frequency detection device is indicative of a density of a fluid within the fluid tank, frequency detection circuitry configured to obtain the frequency from the frequency detection device and output the frequency in a digital form, and an interface for digital communication with an electronic controller, the digital communication comprising transmission of the digital form of the frequency for the electronic controller.

A method is provided for measuring density of a fluid by means of at least one at least sectionally curved measuring tube. The measuring tube is adapted to be flowed through by the fluid and concurrently to be caused to vibrate over a wanted oscillatory length, namely a tube length measured from a first tube end to a second tube end, a length which is greater than a minimum separation of the second tube end from the first tube end. According to the invention, among other things, also a tilt measured value representing an inclination of the at least one measuring tube in the static resting position relative to a local acceleration of gravity is ascertained, in such a manner that such represents an angle of intersection between a direction vector of an imaginary first reference axis (y-axis) and a direction vector of an imaginary second reference axis (g-axis). The first reference axis is so selected that it is perpendicular to an imaginary third reference axis (z-axis) imaginarily connecting the first tube end and the second tube end and points in the direction of a peak of the at least one measuring tube farthest from the third reference axis in the static resting position, while the second reference axis is so selected that it extends through a shared intersection of the first and third reference axes and points in the vertical direction, namely in the direction of the local acceleration of gravity. The tilt measured value is used together with a parameter measured value representing an oscillation frequency of the at least one measuring tube for ascertaining at least one density measured value representing the density of the fluid.

A method for determining and/or monitoring a process variable of a medium using a vibronic sensor includes: exciting a mechanically vibratable unit to vibrate in a first vibration mode via a drive/receiving unit using a first excitation signal; receiving and converting the vibrations of the first vibration mode into a first reception signal; generating the first excitation signal based on the first reception signal; determining the process variable from the first reception signal; exciting the vibratable unit to vibrate in a second vibration mode via the drive/receiving unit via a second excitation signal; receiving and converting the vibrations the second vibration mode into a second reception signal, where the second excitation signal is generated based on the second reception signal; and compensating for an influence of a temperature of the medium on the first reception signal using the second reception signal.

A Coriolis mass flow measuring device and/or density measuring device (100) includes two bent measuring tubes (110a, 110b), which extend mirror symmetrically to a first mirror plane between the measuring tubes, an actuator arrangement (140) and at least one sensor arrangement (142a, 142b); at the inlet end and at the outlet end, in each case, a collector (120a, 120a), with which the measuring tubes are joined, wherein the collectors (120a, 120b) each fulfill the functionality of a node plate; a support body (124), which connects the collectors (120a, 120b) rigidly with one another; and inlet end and outlet end, in each case, at least one plate-shaped coupler (132a, 132b, 134a, 134b), which connect the measuring tubes pairwise with one another, in order to form an oscillator, wherein the couplers have tube openings for measuring tubes, wherein the measuring tubes are connected at least sectionally with the couplers, wherein inlet end and outlet end, in each case, at least one coupler (132a, 132b, 134a, 134b) has, between the measuring tubes (110a, 110b), a tuning opening (146) for influencing the oscillation characteristics of the oscillator.

A method of controlling a vibration of a vibratory element based on a phase error is provided. The method includes vibrating the vibratory element with a drive signal, receiving a vibration signal from the vibratory element, measuring a phase difference between the drive signal and the vibration signal, determining a phase error between a target phase difference and the measured phase difference, and calculating one or more vibration control terms with the determined phase error.

A vibronic sensor for determining and/or monitoring at least one process variable of a medium in a container. The sensor at least comprising: a unit which can oscillate mechanically; a driving/receiving unit; and an electronic unit. The driving/receiving unit is designed to excite, by means of an electrical excitation signal, mechanical oscillations in the unit which can oscillate mechanically and is designed to receive the mechanical oscillations of the unit which can oscillate mechanically, and to convert them into an electrical receiving signal. The electronic unit is designed to generate the excitation signal on the basis of the receiving signal and to determine the at least one process variable from the receiving signal; The electronic unit comprises at least one adaptive filter; and the electronic unit is designed to set the filter characteristic of the adaptive filter in such a way that there is a target phase shift between the excitation signal and the receiving signal.

A measuring transducer for registering and/or monitoring at least one process variable of a flowable medium guided in a pipeline, which at least includes: a housing module, which is mechanically coupled with the pipeline via an inlet end and an outlet end, and a sensor module having at least one measuring tube held oscillatably at least partially in the housing module and caused, at least at times, to oscillate. The at least one component of the housing module and/or of the sensor module is manufactured by means of a generative method and method for manufacturing at least one component of a measuring transducer, which method includes manufacturing the at least one component by means of a primary forming process, especially by means of a layered applying and/or melting-on of a powder, especially a metal powder, based on a digital data set, which gives at least the shape and/or the material and/or the structure of the at least one component.