Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 409)

Spindles
Chapter 17
17-11
Important: A spindle orient is also sometimes automatically requested by
the control when performing some of the drilling cycles described in
chapter 26. This drilling cycle orient orients to either the AMP-defined
position if using a closed-loop orient type or to the position defined as the
open-loop orient position.
Important: In systems allowing multiple spindles (9/260 ad 9/290), only
one M19 code can be in a block. If two or more M19 codes appear in one
block, e.g., M19.2 M19#, this error message appears, “ONLY ONE M19
ALLOWED PER BLOCK.”
Refer to your system installer’s documentation to determine which orient
your system is equipped to perform. This manual assumes that a
closed-loop type orient is available. If an open-loop orient is used, refer to
the system installer’s documentation for details on its operation, as it is
highly PAL dependant.
Both open- and closed-loop spindle orients can be requested either by
programming the appropriate spindle orient code (M19, M19.2, M19.3) in
a program block, or by requesting one through PAL. If closed-loop orient
is requested through PAL, the orient angle is fixed at the default orient
angle preset by the system installer in AMP.
If a closed-loop orient is requested by programming the appropriate
spindle orient code (M19, M19.2, M19.3), the option exists to orient the
spindle to the AMP-defined orient position or to a position programmed
with an S parameter in the M19 block. The S parameter defines an angle
at which the spindle is positioned relative to an angle of zero that is fixed
for a specific machine. Refer to the documentation prepared by the system
installer. This S parameter always programs an absolute angular position.
The angle programmed is not affected by incremental or absolute
programming mode (if open-loop orient is being used, the value
programmed with the S parameter is ignored).
The M19 code is modal. However, each time it is necessary to orient to a
specific angle, an M19 with an S-word must be programmed.
Programming an S-word alone replaces the current modal spindle speed
used later when the M19 mode is canceled. Cancel the M19 spindle orient
by programming one of the other spindle mode M-codes.