Abstract: A digital control loop is provided in which analog signals supplied by a tachometer, driven by an electric motor, are digitally evaluated, that is are compared with a reference value existing in digital form, and a deviation from the reference is employed for controlling the adjustment of an element, a thyristor preferably a triac, by way of an adjusting value generator which is likewise designed as a digital circuit. The speed control regulator can be designed both with an integral control behavior, and a differential control behavior, as well as being designed with a proportional control behavior and combinations thereof.