Patent ID: 7089804

Claim:
A method for measuring a flow rate (v) or a mass flow of a fluid, in particular for measuring hot water supply in the private, public or industrial sector, in which the fluid is guided over a sensor element, which has a heating means for inducing temperature changes and a sensor means for determining its temperature, wherein at least from time to time the heating means is operated with a heating power (P) in the form of heating pulses and a flow-dependent threshold value time (t S ) is measured at the sensor means until a preset temperature threshold value (T S ) is reached, wherein during at least some of the heating pulses a non-constant heating power (P) with a substantially sublinear build-up dynamics (P(t)) as a function of time (t) is selected in order to at least partially compensate a nonlinear behaviour of the threshold value time (t S ) as a function of the flow rate (v).