leg 20 is lower than the preset value the conclusion may be drawn that this must result from a reduced free radius r and therefore must indicate the presence of a yarn body remnant 30 in the corresponding spinning centrifuge 14 a signal assigned to the respective work station 12 is provided via the comparator 48 to the respective output 52 so that the delivery of roving material to the respective work station 12 u2032 is directly interrupted by means of the slubbing stop device 54 which is known and therefore not represented or explained in greater detail in accordance with a further variation a comparison of each respective rotary frequency for a given work station with each other of the rotary frequencies f g of the yarn legs 20 of the work stations 12 can be performed by means of the comparator 48 it will therefore be clear from the above disclosure of the present invention that it is thereby possible directly following the start of a spinning process of the pot spinning machine 10 to detect whether as indicated by means of the example of the work station 12 u2032 in fig1 a yarn body remnant 30 is still present in one of the spinning centrifuges 14 it is then possible to remove the respective work station 12 u2032 immediately from production and clean it the spinning process is preferably continued at the other work stations 12 12 u2033 etc and the affected work station 12 u2032 may be later actuated after being cleaned by means of the method of the present invention it is achieved that all work stations 12 are fully available again at the time of the next.