Patent ID: 7073379

Claim:
A method for fill level measurement with an arrangement for fill level measurement having a fill level measuring device arranged on the container, and operating according to the travel time principle, a material flow apparatus for registering or recording a filling and/or emptying of the container, and an auxiliary unit, which by means of the filling and/or emptying registered or recorded by said material flow apparatus determines the instantaneous change in fill level (V L ) or the instantaneous material flow rate, the method comprising the steps of: transmitting a send-signal (S) to the fill substance; receiving the echo-signal (E) of the send-signal; determining at least one echo (E) of the echo-signal (E); determining a provisional fill level (L E ) from the travel time (t E ) of this, respectively these, echoes (E); determining a measured change (V(E)) in the fill level from the provisional fill level (L E ) and at least one other fill level (L) measured in a previous measuring cycle; determining a deviation (Î”(V(E); V L ) between the measured change in fill level (V(E)) and the instantaneous change in fill level (V L ); determining at least one other echo (Eâ€²) as probably the echo (Eâ€²) reflected on the upper surface of the fill substance when the deviation (Î”(V(E); V L ) exceeds a predetermined upper limit (Î” M ); and repeating said last determination until an echo (E) is found for which the deviation (Î”(V(E); V L ) lies below the predetermined upper limit (Î” M ), and the provisional fill level (L E ) corresponding to this echo (E) is then accepted as the measured fill level (L), or until a terminating condition (X) occurs.