servo drive speed

hello.

i have an ac servo drive with 5000:1 "speed control range",maximum 10v
analog input setpoint and the motor connected to it is 2000rpm.
this means that the minimum speed of motor is 2000/5000= .4 rpm and the minimum allowable analog setpoint to the drive will be 2mv and below .4 rpm the motor can not deliver enough torque and will be stopped under load.

Do you confirm my understanding about "speed control range"?

best regards.

A servo motor should be capable of developing full torque at zero RPM if everything is functioning correctly. What you are describing sounds more like a conventional inverter drive with an induction motor. They will not develop torque at low RPM no matter what you do.

hello.

but in technical specifications of ac servo drives there is something with name of
"speed control range".
what that means?

best regards.

I suspect that what it actually means depends entirely on the manufacturer and the tech writer who wrote the specs. My guess would be that it means that their analog input A/D converter.divides the 0-10 volt signal into 5000 points. That would make your 0.4 rpm = .002 volts value correct, but it doesn't explain the lack of torque.