Hi,
try to rigid tapping and in that case you trust the good closed loop system from the servo to don't keep up with Z and do not loose power. Is it correct?
Yes, the closed loop applies to the servo and servo drive. You signal the drive where you want the servo to be and the servo/servo drive takes itself
there. In some respects its like an open loop stepper, you signal a certain number of steps in a given direction and the stepper drive drives
the stepper to that location....assuming no loss of steps. A servo has feedback so that it is much more certain of arriving at the commanded location,
and if it can't for any reason it will fault 'following error' and alarm out.
You could signal the drive, one pulse = one revolution, but it would be very coarse. All AC servos have the principle of electronic gearing.
It allows that you can signal the drive at one rate, say 1324 pulse per rev, but the servo encoder is 10,000 pulse per rev. Electronic gearing allows
very great flexibility in application of a servo.
Craig