Abstract: A method for operating an electric motor with at least two motor terminals that are driven by a control device contains the steps of short-circuiting of at least two of the motor terminals of the electric motor by the control device; measurement of the motor phase currents at the short-circuited motor terminals; and identification of a standstill of the electric motor if a magnitude and/or a frequency of the motor phase currents measured lies below a predefined limit value. In the case of such a reliable identification of the standstill of the electric motor, an enable signal can then advantageously be generated in order, by way of example, to enable access to an apparatus driven by the electric motor.

Abstract: A motor controller for controlling at least one electric motor has an operating signal generator for generating an operating control signal for the at least one electric motor and also a sound signal generator for generating a sound control signal. A mixer superimposes the sound control signal on the operating control signal in order to obtain a control signal for the at least one electric motor. It is then possible to dispense with loudspeakers and the like in the appliance which contains an electric motor with such a motor controller in order to output, for example, signal tones which indicate an operating state of the appliance to the user.

Abstract: A method for operating an electric motor with at least two motor terminals that are driven by a control device contains the steps of short-circuiting of at least two of the motor terminals of the electric motor by the control device; measurement of the motor phase currents at the short-circuited motor terminals; and identification of a standstill of the electric motor if a magnitude and/or a frequency of the motor phase currents measured lies below a predefined limit value. In the case of such a reliable identification of the standstill of the electric motor, an enable signal can then advantageously be generated in order, by way of example, to enable access to an apparatus driven by the electric motor.

Abstract: A motor controller for controlling at least one electric motor has an operating signal generator for generating an operating control signal for the at least one electric motor and also a sound signal generator for generating a sound control signal. A mixer superimposes the sound control signal on the operating control signal in order to obtain a control signal for the at least one electric motor. It is then possible to dispense with loudspeakers and the like in the appliance which contains an electric motor with such a motor controller in order to output, for example, signal tones which indicate an operating state of the appliance to the user.