Endress + Hauser Flowtec Ag

Fred Kappertz

Frank Voigt

Daniel Wild

Günther Bähr

Thomas Küng

Florent Tschambser

Markus Rüfenacht

Lars Dreher

Thomas KÜNG

Markus RÜFENACHT

Günther BÄHR

Disclosed is a method for commissioning a magneto-inductive flow measuring device having means for producing a magnetic field and at least one measuring electrode pair for sensing a potential difference in a medium. The method includes a settling of the means during a settling time for stabilizing the magnetic field. During the settling time a first voltage time function is applied to the means, wherein after the settling time a measuring time begins, wherein during the measuring time a second voltage time function is applied to the means, wherein the settling time is divided into first time intervals, each of which has a duration, wherein the measuring time is divided into second time intervals, each of which has a duration, wherein an average value of all first interval durations is always less than an average value of all second interval durations.

Method for commissioning a magnetic inductive flowmeter, and a magnetic inductive flowmeter

A method for ascertaining volume- or mass-flow of a magnetically conductive medium flowing through a magneto-inductive, flow-measuring device having a predetermined nominal-diameter, wherein a periodically alternating, magnetic field is caused to pass through the flow-measuring device, the actual rise time, until a constant magnitude of the magnetic field is reached, is ascertained, the actual rise time is compared with a desired rise time ascertained in the case of flow of a reference medium through the flow-measuring device, and, on the basis of a difference between actual rise time and desired rise time, a measurement error is ascertained and the actually measured volume- or mass-flow of the magnetically conductive medium is so corrected, that the measurement error is canceled.

Method and apparatus for ascertaining volume- or mass-flow

A flow sensor includes: A measuring tube for the conveying of an electrically conductive fluid; a magnetic circuit arrangement arranged on the measuring tube for producing and guiding a magnetic field, which induces an electric field in the flowing fluid; and measuring electrodes for the tapping of a voltage of the electric field. The measuring tube includes a carrier tube and liner, especially a tubular liner, of insulating material, accommodated in a lumen of the carrier tube. A support skeleton may serve for stabilization is embedded in the liner. The carrier tube additionally has at least a first groove formed in a wall of the carrier tube and open towards the lumen of the carrier tube, whereby, on the one hand, the tendency of the liner and/or of the possibly present support skeleton towards crack formation upon temperature changes, especially in the case of cooling, can be considerably reduced, and, on the other hand, a rotation or displacement of the support skeleton in the carrier tube, especially in the case of possible material shrinkage, can be effectively prevented.

Magnetically inductive cross-flow sensor and method for the production thereof

An apparatus for measuring and/or monitoring the flow of a medium to be measured, which is flowing through a measuring tube in the direction of the longitudinal axis of the measuring tube. The apparatus includes: A magnet arrangement which produces a magnetic field passing through the measuring tube and running essentially transversely to the longitudinal axis of the measuring tube; two measuring electrodes which are galvanically or capacitively coupled with the medium to be measured and which are arranged in such a manner that a measurement voltage is induced in them, evoked by the medium to be measured; an evaluation control unit, which, on the basis of the measurement voltage induced in the measurement electrodes, provides information concerning the volume flow of the medium to be measured in the measuring tube; wherein connecting lines, or signal lines, as the case may be, are provided, by way of which the measurement signals are led between the measurement electrodes and the control/evaluation unit. In order to be able to arrange the signal lines in a space saving manner, the signal lines are arranged in an essentially planar structure.

Apparatus for measuring and/or monitoring flow of a medium

A flow sensor includes a measuring tube, made of essentially non-ferromagnetic material, for guiding the fluid, a magnetic circuit arrangement arranged on the measuring tube for producing and guiding a magnetic field, which induces in the flowing fluid an electric field, and measuring electrodes for sensing a voltage of the electric field. Additionally, the flow sensor includes an essentially rigid support frame for holding the measuring tube and for holding an electronics housing connected to the flow sensor, wherein measuring tube and support frame are mechanically coupled together on the inlet and outlet ends. For holding the measuring tube in the support frame, at least one connecting element is provided, which is attached to a first end of the measuring tube and to a first end of the support frame corresponding to such end of the measuring tube. The at least one connecting element is so formed and so arranged in the flow sensor, that it is essentially axially flexible, as compared to support frame and measuring tube, in the direction of the longitudinal axis of the measuring tube.

Growing community of inventors

Hochwald, Switzerland

Fred Kappertz