Although the inertia is not a problem for the electric motor with soft starting, it is yes for the drive with frequency inverter. Centrifugal applications require the motor and drive to be sized for the maximum operating speed conditions. Alternative loads shall be sized for minimum operating speed conditions.
From any point of view, actual load data must be provided to all electric motor manufacturers in order to ensure that the motor will be able to start and accelerate the load and work within the specified temperature limits and under all conditions of operation. c1f1c0les hps fortress In most variable speed applications, the maximum operating speed is or is close to the nominal speed of a standard motor, which is directly connected to the mains. Low-speed operations do not share the same mechanical integrity problems as high-speed operations, but they certainly share the problems of bearings, lubrication and cooling. The minimum operating speed must be mentioned in the Data Sheet or Specification, since the engine cooling system is connected closely to its rotation.