Description: In solid mechanics, in the field of rotordynamics, the critical speed is the theoretical angular velocity that excites the natural frequency of a rotating object, such as a shaft, propeller, leadscrew, or gear. ; Name: crit. speed
Description: Speed of rotation at which the frequency of vibration (or its multiples) corresponds to the rotor resonant (lateral or torsional) ; Name: Critical speed
Description: classifies the scope of the protection of the electromagnetic device against direct contact, against insertion of hard foreign objects and/or infiltration through water; Name: Protection type class of the electric motor