Control system for spinning frames, the spinning frames comprising a plurality of spindles, each spindle comprising first drawing rollers configured so as to draw a first roving and thus obtain a first yarn (1211, 1216, 1218), the control system comprising a plurality of control devices (5000, 7000, 9001-900N) associable to the plurality of spindles, each control device (5000, 7000, 9001-900N) comprising: - an optical movement sensor, and - a frequency meter, wherein the optical movement sensor is configured so as to measure the movement of the first yarn (1211, 1216, 1218), wherein the frequency meter is configured so as to receive the signal measured by the optical movement sensor and so as to measure at least one oscillation frequency (Fmax1_int) of the first yarn (1211, 1216, 1218), characterized in that the control system further comprising a controller, wherein the controller comprises: - a device for evaluating the condition of the spindles, configured so as to determine at what spindles of the plurality of spindles the first yarn is present and in a valid yarn state, and - an average value calculator connected to the device for evaluating the condition of the spindles, configured so as to calculate an average value of the revolutions of the spindles at which the first yarn is present and in a valid yarn state, or - a sensor, configured to be positioned on a motor which rotates the spindles, configured so as to measure the average value of revolutions as the value of revolutions of the motor, and - an interval calculator configured so as to calculate an interval based on the average value of revolutions and on a threshold value (SFTG), wherein the interval calculator is connected to the device for evaluating the condition of the spindles so as to provide the value of the interval to the device for evaluating the condition of the spindles, wherein the controller is connected to the plurality of control devices (5000, 7000, 9001-900N) so as to receive the oscillation frequency (Fmax1_int) measured by the respective control device (5000, 7000, 9001-900N), and wherein the device for evaluating the condition of the spindles is configured so as to evaluate as good the spindles whose oscillation frequency is included within the interval, wherein the controller comprises a chronometer, and wherein the device for evaluating the condition of the spindles is configured so as to evaluate as not good the spindles whose oscillation frequency is outside the interval for a predetermined time duration (TFTG) measured by the chronometer and so as to be able to activate an alarm. - an optical movement sensor, and - a frequency meter, - a device for evaluating the condition of the spindles, configured so as to determine at what spindles of the plurality of spindles the first yarn is present and in a valid yarn state, and - an average value calculator connected to the device for evaluating the condition of the spindles, configured so as to calculate an average value of the revolutions of the spindles at which the first yarn is present and in a valid yarn state, or - a sensor, configured to be positioned on a motor which rotates the spindles, configured so as to measure the average value of revolutions as the value of revolutions of the motor, and - an interval calculator configured so as to calculate an interval based on the average value of revolutions and on a threshold value (SFTG),