Description: Critical speed (nk) is the rotational speed at which acting dynamic forces cause a machine component (e. g. shaft, rotor) to vibrate at its natural frequency (also referred to as intrinsic frequency, fi) and can even result in resonant vibrations throughout the entire machine and pump set; 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