Patent ID: 7979227

Claim:
A method for calibrating a measuring device monitoring a measured variable of a measured medium on the basis of at least a first sensor: providing a mapping specification on the basis of which a signal of the first sensor is mapped to a measured value of the measured variable; recording at a point in time a current measured value of the measuring device as a current calibration measured value; supplying to a laboratory reference measuring device a laboratory reference sample of the measured medium having properties of the measured medium which are the same as those at the point in time of the recording of the calibration measured value; ascertaining with the laboratory reference measuring device an actual value of the measured variable on the basis of the laboratory reference sample and making available and storing the actual value as a current laboratory reference measured value; wherein the calibration measured value and the current laboratory reference measured value are stored in a data memory of the measuring device; updating the mapping specification based on the current calibration measured value as well as the current laboratory reference measured value by means of a program stored in a program memory of the measuring device; and at least one, earlier value pair of a calibration measured value and an associated laboratory reference measured value, ascertained in an earlier calibration and stored in the data memory of the measuring device, is taken into consideration for updating the mapping specification by the program.