Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 369)

Axis Motion
Chapter 14
14-11
Determining Rotary Axis Feedrates
The feedrate for a rotary axis is determined in much the same way as linear
axes.
When the control is in rapid mode (G00), the feedrate for the rotary axis is
the rapid feedrate for that axis as set in AMP. Remember that if other axes
are moving in the same block, the feedrate for the block is limited by the
axis that takes the longest time to complete its programmed move at its
rapid speed. (see chapter 18 for details).
When the control is in one of the cutting modes (G01, G02, or G03), the
control uses the programmed feedrate to calculate the angular velocity of
the rotary axis. This feedrate is still limited to the maximum cutting
feedrate (feedrate clamp) as determined in AMP.
When you program in this mode: The rotary feedrate units are in:
G94 feed per minute degrees per minute.
G95 feed per revolution degrees per revolution of the spindle.
In any event, if a rotary axis is programmed in a block with other axis
moves in either rapid (G00) or cutting (G01, G02, or G03) modes, all axes
reach their destinations at the same instant.
CAUTION: When programming a rotary axis remember that
the programmed feedrate is in units of angular velocity. This
means that the actual cutting feedrate depends on the tools
distance from the center of rotation of the rotary axis.
Your system installer has the option of controlling selected axes through
the PAL program. When an axis is under PAL control, the operator and
part program have no control on that axis. Jog commands, as well as part
program commands, are typically ignored unless PAL has been written to
manipulate these values in some manner.
Be aware that it is possible to disable axis position displays on the CRT for
an axis under PAL control. Refer to the documentation provided by your
system installer for details on an axis controlled by PAL.
Important: S--Curve Acc/Dec mode is not available with PAL Axis
Mover.
14.1.5
PAL Axis Mover