The invention relates to a process for locating a rotating drive part using a measuring system which comprises an absolute and an incremental partial measuring system. After the start of rotation, currently absolute position measuring values are determined and transmitted to a downstream evaluation unit until a reference mark reaches a known absolute position. At the reference mark there is a comparison of the measuring values, known from the current absolute position measurement, with the known absolute position and an optionally required adjustment is performed. The reference mark is subsequently used as the reference position for the incremental partial measuring system, the currently absolute position is indicated by the measuring system, and transferred to the evaluation unit in digital form.