A system for operating an electric machine includes: a rotor position sensor to provide a rotor position indication as a function of a rotor position angular range which indicates the position of a rotor of the electric machine; a control unit designed to associate in each case a commutation angular range, which indicates a certain control state for the stator coils, with one or more of the rotor position indications, so that a change in the commutation angular range is triggered by a change in the rotor position indication, and to change an association scheme of the associations between the rotor position indications and the respective commutation ranges as a function of a predefined rotational direction indication which indicates the desired rotational direction.