Abstract: A method for detecting the state of operation of a rotating machine, in particular a centrifugal pump, includes detecting using at least one first temperature sensor a change in temperature in or at least one bearing region of a rotating element of the rotating machine, identifying temperature gradients using an evaluation unit, from a temperature profile generated from the at least one temperature sensor, and identifying a switch-on and/or switch-off process of the rotational movement of the machine on the basis of a characteristic of the ascertained temperature gradient.