Patent ID: 9671339
Date: 2017-06-06
CPC Classifications: G01N

Claim:
1. A method for determining the turbidity of a medium using at least one turbidity sensor for use in process automation, the method comprising: calculating parameters for a noise model for the turbidity sensor; passing transmitted radiation into a medium, wherein the transmitted radiation is converted into received radiation by scattering as a function of turbidity in the medium; converting the received radiation into a scattered light intensity; measuring a chronological sequence of the scattered light intensity; calculating a mean value of the chronological sequence of the scattered light intensity; calculating a turbidity value from the mean value using a calibration model; calculating a noise parameter based on the chronological sequence of the scattered light intensity; calculating a corrected mean value of the chronological sequence of the scattered light intensity using the noise parameter and the noise model; calculating a corrected turbidity value using at least the corrected mean value and the calibration model; calculating a turbidity offset by comparing the turbidity value and the corrected turbidity value; and determining whether the turbidity offset exceeds a threshold, wherein upon determining that the turbidity offset exceeds the threshold, generating a message indicating that the turbidity value contains interference due to an interference variable or an interference source.