Abstract: A lab centrifuge with a rotor carrying vessel supports and a motor with a vertical shaft driving said rotor into rotation, the stator associated with said rotor being supported by elastic supports on a centrifuge base. A shutoff device controls the motor which it shuts off in response to a signal generated by a component affixed to the stator and a component affixed to the base when the stator deviation taking place is found to exceed or match the maximum admissible threshold imbalance. One of the two components is a field generator generating a constant field and the other component is a field intensity detector connected to an analyzer which, upon limit changes in field intensity caused by the deviation, implements shutoff.