US 11,920,972 B2
Monitoring the state of a vibronic sensor
Romuald Girardey, Blotzheim (FR); Raphael Kuhnen, Schliengen (DE); and Izabella Sandor, Schopfheim (DE)
Assigned to Endress+Hauser SE+Co. KG, Maulburg (DE)
Appl. No. 17/602,906
Filed by Endress+Hauser SE+Co. KG, Maulburg (DE)
PCT Filed Mar. 12, 2020, PCT No. PCT/EP2020/056724
§ 371(c)(1), (2) Date Oct. 11, 2021,
PCT Pub. No. WO2020/207699, PCT Pub. Date Oct. 15, 2020.
Claims priority of application No. 10 2019 109 487.9 (DE), filed on Apr. 10, 2019.
Prior Publication US 2022/0196456 A1, Jun. 23, 2022
Int. Cl. G01F 25/20 (2022.01); G01F 23/296 (2022.01)
CPC G01F 25/20 (2022.01) [G01F 23/296 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method for state monitoring of a coil that is a part of a device for determining at least one process variable of a medium in a containment, the method comprising:
supplying the coil with an alternating electrical excitation signal and varying a frequency of the excitation signal from a starting frequency to an ending frequency;
receiving an electrical received signal from the coil during the varying of the frequency of the excitation signal;
measuring a phase shift between the excitation signal and the received signal;
ascertaining a first frequency for the excitation signal such that a first phase shift between the excitation signal and the received signal at the first frequency is less than a predeterminable limit value;
comparing an actual value for the first frequency with a desired value for the first frequency;
ascertaining a state indicator for the coil based on a deviation of the actual value of the first frequency from the desired value of the first frequency; and
ascertaining information regarding an extent of damage in the coil based on the deviation between the actual value of the first frequency and the desired value of the first frequency.