Control unit for a valve arrangement, the control unit comprising an output device, the valve arrangement comprising an adjustable valve element (1, 2, 3), wherein the adjustable valve element (1, 2, 3) has an open and a closed position, the valve arrangement also comprising an actuator and a sensor, wherein the actuator is coupled directly and the sensor is coupled directly or indirectly to the valve element (1, 2, 3), wherein the actuator and the sensor can be communicatively connected to the control unit, and the control unit is configured to control the actuator such that it performs a number of valve cycles, wherein a valve cycle comprises adjusting the valve element (1, 2, 3) into its open position and adjusting the valve element (1, 2, 3) into its closed position, wherein the sensor is configured to generate a signal corresponding to a position of the valve element (1, 2, 3), wherein the control unit is configured to control the actuator such that it performs a first number of valve cycles with at least one valve cycle, to read out a first signal from the sensor following performance of the first number of valve cycles and to process it to form a first measured value of a position of the valve element (1, 2, 3), and to control the actuator following reading out of the first signal such that it performs a second number of valve cycles with at least one valve cycle, and to read out a second signal from the sensor following performance of the second number of valve cycles and to process it to form a second measured value of a position of the valve element (1, 2, 3), and, based on the first and the second measured values and the second number of valve cycles, to determine a degree of wear and compare it with a predefined threshold value and to output a predefined output signal using the output device if the degree of wear exceeds the predefined threshold value, characterised in that the output device of the control unit can be communicatively connected to the actuator and the predefined output signal is an interlock signal, on receipt of which by the actuator, the actuator locks, and the control unit is configured to output the predefined output signal using the output device, by the control unit outputting the interlock signal to the actuator. an actuator and a sensor, wherein the actuator is coupled directly and the sensor is coupled directly or indirectly to the valve element (1, 2, 3), wherein the actuator and the sensor can be communicatively connected to the control unit, and the control unit is configured to control the actuator such that it performs a number of valve cycles, wherein a valve cycle comprises adjusting the valve element (1, 2, 3) into its open position and adjusting the valve element (1, 2, 3) into its closed position, wherein the sensor is configured to generate a signal corresponding to a position of the valve element (1, 2, 3), wherein the control unit is configured to control the actuator such that it performs a first number of valve cycles with at least one valve cycle, to read out a first signal from the sensor following performance of the first number of valve cycles and to process it to form a first measured value of a position of the valve element (1, 2, 3), and to control the actuator following reading out of the first signal such that it performs a second number of valve cycles with at least one valve cycle, and to read out a second signal from the sensor following performance of the second number of valve cycles and to process it to form a second measured value of a position of the valve element (1, 2, 3), and, based on the first and the second measured values and the second number of valve cycles, to determine a degree of wear and compare it with a predefined threshold value and to output a predefined output signal using the output device if the degree of wear exceeds the predefined threshold value, characterised in that the output device of the control unit can be communicatively connected to the actuator and the predefined output signal is an interlock signal, on receipt of which by the actuator, the actuator locks, and the control unit is configured to output the predefined output signal using the output device, by the control unit outputting the interlock signal to the actuator.