CORIOLIS MASS FLOW METER AND METHOD OF MONITORING A CORIOLIS MASS FLOW METER

Monitoring a mass flowmeter includes ascertaining a resonant frequency of a bending oscillation, wanted mode, and a density measured value of a medium as a function of the frequency. A bending oscillation is excited outside of resonance with an excitation signal having an amplitude and a frequency (μ times the resonant frequency of the bending oscillation, wanted mode). An amplitude of a sensor signal of the bending oscillation outside of resonance is ascertained. A value of an integrity function of the measuring tube depending on a ratio of the sensor signal amplitude to the excitation signal amplitude of the bending oscillation is ascertained. The integrity function depends further on a density term of a transfer function that models contributions of a plurality of oscillation modes to the sensor signal. This function is reduced to reference conditions, and/or transformed to an integrity value, which has no cross sensitivities for media density.