| 摘要 |
Method for operating an apparatus for determining and/or monitoring at least one physical process variable for a medium having an oscillating unit (2), wherein the oscillating unit is prompted to oscillate by means of a first frequency search process within a predetermined frequency band in the operating range of the oscillating unit at successive discrete excitation frequencies of rising or falling frequency, wherein the relevant oscillations in the oscillating unit are received and wherein a first excitation frequency (f1) is ascertained for which, during the first frequency search process, at least one prescribable criterion is satisfied, wherein the oscillating unit is prompted by means of a second frequency search process, wherein the frequency band is swept in the opposite direction in comparison with the first frequency search process, wherein a second excitation frequency (f2) is ascertained for which, during the second frequency search process, the at least one prescribable criterion is satisfied, and wherein a measurement frequency (fm) for determining and/or monitoring at least one process variable is determined from the first excitation frequency (f1) and the second excitation frequency (f2) by means of averaging. |
