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S811+ Soft Stop ramp down

Typically,  the stop ramp is selected because the application will not coast to a stop in a smooth manner. Similar to the ramp start sequence, the motor will be under load during the stop ramp. When a soft stop is applied to a motor, the voltage is ramped down and we are self-analyze and self-adjusting base on the current, and counter EMF. As the voltage is ramped down, the maximum torque available from the motor reduces until the motor cannot produce enough torque to keep the motor running. At this point, the motor begins to stall and slows down to the point where the torque produced by the motor is equal to the torque required by the application.  As the motor slows, its impedance drops, and the current will rise significantly.  The current during a soft stop will be a little less than the current during start, but can be present for significantly longer, depending on the soft stop time selected.

 

S811+ /S801+ Product Overview

Overview of soft stop functioning on S811+ soft starters