Coriolis mass flow meter

A Coriolis mass flow meter for measuring a mass flow of a fluid substance, the Coriolis mass flow meter comprising:

• a measuring transducer, including:
• a vibration element;
• an exciter assembly;
• and
• a sensor assembly, wherein the measuring transducer is configured to conduct the substance to be measured therethrough;
• and
• an electronic transformer circuit electrically coupled to the exciter assembly and to the sensor assembly, wherein the electronic transformer circuit includes a microprocessor and a non-volatile electronic data memory configured to store digital data even without an applied operating voltage,
• wherein the vibration element is configured to be contacted by the fluid substance and to be vibrated at the same time,
• wherein the exciter assembly is configured to convert electric power fed to the exciter assembly into mechanical power causing forced mechanical vibrations of the vibration element,
• wherein the transformer circuit is configured to generate an electric driver signal and feed electric power to the exciter assembly using the driver signal, such that the vibration element executes forced mechanical vibrations at a used frequency, which is a vibration frequency specified by the electric driver signal, wherein the mechanical vibrations are suitable for producing, in the fluid substance, Coriolis forces based on the mass flow,
• wherein to detect mechanical vibrations of the vibration element, the sensor assembly includes an electrodynamic first vibration sensor and an electrodynamic second vibration sensor that is structurally identical to the first vibration sensor,
• wherein the first vibration sensor is configured to convert vibrational movements of the vibration element at a first measurement point into an electric first vibration measurement signal of the sensor assembly such that the first vibration measurement signal includes a first signal component, which is an AC voltage component at a frequency corresponding to the used frequency and at an amplitude dependent on the used frequency and a first magnetic flux through the first vibration sensor,
• wherein the second vibration sensor is configured to convert vibrational movements of the vibration element at a second measurement point remote from the first measurement point into an electric second vibration measurement signal of the sensor assembly such that the second vibration measurement signal includes a second signal component, which is an AC voltage component at a frequency corresponding to the used frequency and at an amplitude dependent on the used frequency and a second magnetic flux through the second vibration sensor, and
• wherein the transformer circuit is configured to receive and evaluate the first and second vibration measurement signals both to ascertain the mass flow measurement values and to calculate characteristic number values for at least one sensor characteristic number, such that said sensor characteristic number represents a change rate at which at least one of the amplitudes of the first and second signal components changes over time.