Patent ID: 7847564

Claim:
A probe for measuring the conductivity of a solution, comprising an annular conduit ( 2 ) having an inlet ( 3 ) and an outlet ( 4 ) for the solution and forming a cell ( 2 a ) for measuring the conductivity, a first and a second coil ( 7 , 22 ) fitted round the conduit ( 2 ), an energizing circuit ( 8 ) that generates a voltage (Vr 1 ) for energizing the first coil ( 7 ), current reading means ( 43 ) associated with the second coil ( 22 ) for reading a current (I) circulating in the second coil ( 22 ), the second coil ( 22 ) being mutually concatenated with the first coil ( 7 ) through an electromagnetic flux (F) generated by the first coil ( 7 ) and through the solution circulating in the conduit ( 2 ), the probe being characterized in that it comprises: a temperature transducer ( 6 ) for sensing a temperature of the solution within the conduit ( 2 ) at a location where the solution experiences a minimum turbulence; a feedback winding ( 11 ) in which an electric current is induced by the electromagnetic flux (F) generated by the first coil ( 7 ); and compensation means ( 44 ) associated with the first coil ( 7 ) to perform a comparison of a reference voltage (Vr) to a feedback voltage (Vf) across the feedback winding ( 11 ) and vary the voltage (Vr 1 ) generated by the energizing circuit ( 8 ) based on the comparison to maintain the electromagnetic flux (F) generated by the first coil ( 7 ) at a substantially-constant value, the compensation means ( 44 ) comprising a computerized unit ( 29 ) for determining an offset correction to the conductivity value measured with the cell ( 2 a ) as a function of the temperature of the solution as sensed by the temperature transducer ( 6 ) to output a calibrated conductivity value that is a function of both the temperature of the solution and the feedback voltage (Vf) across the feedback winding ( 11 ).