Patent ID: 7134330

Claim:
An apparatus for capacitive determination and/or monitoring of the fill level of a medium in a container, comprising: at least one fill level probe; at least one electronic field device, which communicates with said at least one fill level probe, and generates a voltage trigger signal (sig 1 ) which is converted into a sine-wave trigger voltage (U 1 ) for triggering said at least one fill level probe, and which receives and evaluates a measurement current (I 2 ) of said at least one fill level probe; and at least one microprocessor in said at least one electronic field device, said at least one microprocessor generates the voltage trigger signal (sig 1 ) samples a voltage signal (U 2 ) that is proportional to the measurement current (I 2 ) directly, evaluates the sampled course over time of the voltage signal (U 2 ) that is proportional to the measurement current (I 2 ), samples the sine-wave trigger voltage (U 1 ) directly, and uses the sine-wave trigger voltage (U 1 ) for referencing in evaluating the measurement current (I 2 ).