Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 339)

Spindle 1 Parameters
Chapter 12
12-11
For example, if it takes 20 msec for a small change in spindle speed (such
as from 0 to 5 rpm) and 160 msec for the maximum change in spindle
speed (such as from 0 to 4000 rpm), a good value to enter here would be
the average transition time, 90 msec.
Refer to the discussion for the parameter Spindle Deviation Tolerance.
If spindle DAC output ramping is on:
This parameter specifies:
the spindle acceleration /declaration time to be used by the control for
simulated feedback. Simulated feedback is explained with the
parameter Spindle Deviation Tolerance. If you have the solid tapping
feature option, enter a value for this parameter that closely matches the
spindle acc/dec curve established by the solid tapping parameters (see
page 12-4).
if your system does not have the solid tapping feature this parameter
specifies the duration of the spindle ramp (see page 12-4). This is also
the same value the control uses for simulated feedback.
Spindle Parameter
Number
1 [70]
Range
20 to 400 msec
Notes
Simulated feedback allows the control to perform “feed per revolution”
moves on machines that do not have position feedback from the spindle.
If the spindle has position feedback and the software option for spindle
speed deviation detection has been installed, simulated feedback is also
used for spindle speed deviation detection.
This parameter must be set for each spindle axis.