Inverter duty motors withstand the reflected wave phenomena which, if your soft-start unit has DC bus, could deliver nearly twice the DC bus voltage(2 x 800) to your motor. A cheaper alternative to an inverter duty motor may be load filters (reactor & capacitor unit) installed between the controller and motor. They are available from VFD manufacturers.They also make a special device mounted at the motor terminals to absorb the spikes.
[This message has been edited by Redsy (edited 08-22-2001).]
