VSD as the final element instead of a Control Valve?

Flow controller FIC sends an output between 0-100% to a Flow control valve FCV to throttle a pump discharge flow.
The existing FCV is straight forward, Valve will be closed at 0% output and open at 100% output.

I want to use a VSD as the final element to control flow instead of the FCV. My question is which motor speed corresponds to a 0% Flow controller output to VSD?

Should it be :
1. 0 RPM @ 0% --> Flow is stopped.
2. The minimum RPM for motor @ 0% ? (a minimum RPM prevents motor overheating)
In this case, the flow is not stopped because the minimum RPM is not not zero, so I have to figure a way out to stop the flow.

P.S. I am a beginner.
 
Change the low limit on the flow controller to be equivalent to the minimum motor RPM, eg 40% for 20Hz (50Hz supply). If your motor does not have forced cooling I would typically have 20Hz as minimum, depends on motor design. If flow is possible with the motor not powered you would need an additional on/off valve to stop the flow
 
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