Patent ID: 7905144

Claim:
A measuring device for determination of flow amounts, dV(z), of electrically conducting liquids having conductivity LF, for flow through a container in which the liquid level varies in the vertical direction (z-direction), which device is comprised of: a container having: a bottom wall, a liquid inlet, and a liquid outlet; and a conductivity measuring device comprised of the following components: a voltage source; an evaluation device; and at least one measuring element, which measuring element: is disposed in the container and is connected to the evaluation device; and has at least two electrodes which extend in the z-direction, which electrodes are disposed a distance apart in a direction perpendicular to the z-direction, wherewith Z max represents a distance from a first end (lower end) of the electrode (at z=0) to a second end (upper end) of the electrode; wherein at time intervals t i −t i−1 (for i=1 . . . n), the conductivity measuring device delivers measurement values M t i ( V )= M ( V ( z )) ˜LF·f M ( V ( z )) wherein at least the container or the conductivity measuring device or a combination thereof is configured such that it is or they are describable by at least one parameter function dependent on V(z), f P I (V(z)) (for I=1 . . . m), so that the following applies: f M ( V ( z ))˜ f ( f P I ( V ( z ) for I= 1 . . . m ))˜ b M V(z) , where b M is a number which is not equal to zero or 1; wherein the evaluation device is configured at least so as to be able to deliver quotients of the measured values and to obtain logarithms of the quotients.