Description: Rotor resonant frequency calculated assuming that the rotor is supported only in the bearings and that the bearings have infinite stiffness; Name: crit speed (dry)
Description: Rotor resonant frequency calculated considering the additional support and damping produced by the action of the pumped fluid within rotor  ; Name: Wet 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