Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 470)

Programming Feedrates
Chapter 18
18-22
The system installer sets these values in AMP:
angle Ap in AMP in 1 degree increments within a range of 1-90 degrees
range in which the automatic corner override function is active --
essentially, the values of “a” and “c” in absolute distance measured
along the tool path for “b”
override value in 1-percent increments within a range of 1-100 percent.
To use an exact stop function while the automatic corner override mode
(G62) is active, use the G09 instead of the G61. This is because G61 and
G62 belong to the same G modal group and will cancel each other if
programmed. Be aware that G09 is non-modal.
The system installer has the ability to change the rate in which a spindle is
accelerated. AMP allows the option of setting RAMP to occur in 2 ms
intervals during one system scan or as an immediate step. By writing the
appropriate PAL, the system installer may also, in effect, generate a spindle
“ramp” for even longer spindle acceleration ramps. Refer to
documentation prepared by the system installer.
In the control’s default mode (G36), the Acc/Dec feature in some cases
limits the feedrate below your programmed feedrate. This occurs when the
length of the block is relatively short relative to the length of time
necessary to properly decelerate the axis to a stop. In the default mode
(G36), the control limits the feedrate of any block to the maximum speed
from which it can properly decelerate all the axes to a stop before that
block ends. For example, consider the following velocity profile of a
block moving from X5 to X5.1.
18.4.6
Spindle Acceleration (Ramp)
18.4.7
Short Block Acc/Dec
G36, G36.1