Method for detecting a measurement error when measuring a media property of a medium by means of a field device of measurement and automation technology and an ultrasound flow meter or ultrasound level meter used to implement the method

摘要

Method (100) for detecting a measurement error when measuring a media property of a medium in a container of a medium by means of a field device of measurement and automation technology, wherein in a first method step (101) at least one measurement of at least one first media property (M1) by means of the field device is carried out, an electronic measuring / operating circuit (77) each providing at least one measured value (MF) of the first media property, in a second method step (102) at least one second media property (M2) different from the at least one first media property directly by means of in each case at least of a sensor provided for this purpose, the electronic measuring / operating circuit (77) providing at least one sensor measured value (SM) on the basis of a measurement signal generated by the sensor; in a third method step (103) a known relationship (Z) between the at least one first en media property and the at least one second media property is used to calculate the at least one second media property from the at least one first media property by means of the electronic measuring / operating circuit, the electronic measuring / operating circuit each providing at least one calculation value (BW); in a fourth method step (104), by comparing the at least one sensor measured value with the at least one calculated value, a statement about the functionality of the corresponding sensor or the measuring device is derived, characterized in that the field device is an ultrasonic flow measuring device and measures the speed of sound of the medium, wherein the sensor measures temperature, pressure, density, thermal conductivity, compressibility or adiabatic coefficient, wherein the ultrasonic flow meter works according to the time difference principle, and wherein the container is a measuring tube through which ch measuring tube the medium flows.