US 8,576,399 B2Granted

Method and apparatus for turbidity measurement

AssigneeEndress + Hauser Conducta Gesellschaft für Mess- und Regeltechnik mbH + Co. KG

InventorsEdin Andelic, Rudiger Frank

Life of this patent

Estimating the term…

Loading patent…

Abstract

A method for turbidity measurement in a measured medium uses a turbidity sensor, which comprises at least a first and a second emitter and at least a first and a second detector. The first and the second emitters are excited one after the other to produce light signals directed into the measured medium; wherein each light signal travels along a first propagation path through the measured medium to the first detector, and is converted by such into a first detector signal; and travels along a second propagation path through the measured medium to the second detector, and is converted by such into a second detector signal. A turbidity value is ascertained based on the first and the second detector signals; wherein, by means of at least one additional detector, to which at least one of the light signals travels along an additional propagation path, an additional detector signal is ascertained, and, on the basis of the additional detector signal, the turbidity value is checked as regards its plausibility.

Claims20

Dependent claims

A method for turbidity measurement in a measured medium by means of an apparatus comprising:

at least a first and a second emitter, and at least a first detector and a second detector, comprising the steps of:
exciting the first and the second emitter one after the other, in order to produce light signals directed into the measured medium, wherein each light signal travels along a first propagation path through the measured medium to the first detector, and is converted by such into a first detector signal;
and travels along a second propagation path through the measured medium to the second detector, and is converted by such into a second detector signal;
and
ascertaining a turbidity value based on the first and the second detector signals by means of at least one additional detector, to which at least one of the light signals travels along an additional propagation path, a supplemental detector signal is ascertained, and on the basis of the additional detector signal, the turbidity value is checked as regards its plausibility, wherein:
the plausibility is a probability with which the turbidity value reflects the actual turbidity of the measured medium;
and
the at least one additional detector receives light signal of at least one emitter along a propagation path outside of the measured medium.

5 more elements

An apparatus for measuring turbidity of a measured medium, comprising:

at least a first and a second emitter wherein the first and second emitter are excited one after the other:
at least a first and a second detector, said at least a first and at least a second emitter and said at least a first and at least a second detector are arranged with respect to one another in such a manner, that light signals produced by said at least a first and at least a second emitter and directed into the measured medium travel along a first propagation path through the measured medium to said at least the first detector, and along a second propagation path through the measured medium to said at least said second detector;
and
at least one additional detector, which is arranged in such a manner, that a light signal produced by said at least one first and at least one second emitter travels along an additional propagation path to said at least one additional detector, wherein:
said at least one additional detector is arranged with respect to said at least a first and said at least a second emitter in such a way, that it receives a light signal of at least one of said at least a first and said at least a second emitter along a propagation path outside of the measured medium;
and an evaluating unit, which is designed to determine a turbidity value of the measured medium from detector signals of said at least one first and at least one second detector;
said evaluating unit is furthermore designed to check, on basis of a detector signal produced by said at least one additional detector, the turbidity value as regards its plausibility;
and
the plausibility is a probability with which the turbidity value reflects the actual turbidity of the measured medium.

6 more elements

Dependencies are inferred from the claim text.