Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 445)

Spindles
Chapter 17
17-9
Deactivate Spindle Synchronization (G45)
Use G45 to deactivate the synchronized spindle feature. When
synchronization is deactivated, the follower spindle will remain in the
same state (M03, M04, M05, or M19) and at the last programmed speed
for controlling spindle until you change the program settings or if your
system installer writes PAL to recommand the spindle.
In a multiprocess system, if the spindles are synchronized, and an
end--of--program (M02) is reached on the process that is synchronizing the
spindles, both spindles will obey the end--of--program commands. Then
synchronization will be disabled.
The format for the G45 cycle is as follows:
G45;
Important: No other program letters are allowed in the G45 block except
auxiliary letters and system installer M--codes.
When using the synchronized spindle feature, remember:
you cannot retrace through a synchronization block (G45, G46, or
G46.1). However, you can retrace through blocks where
synchronization was already active.
in dual--process systems, both spindles used for synchronization
must be configured in the process that is programming spindle
synchronization. Shared spindles are acceptable if they area
already controlled by the process requesting synchronization.
gear changes are not allowed during synchronization. If spindle
speeds exceed the gear range of either spindle, the spindles will be
limited to the more restrictive spindle’s values.
due to the servo switch from open-- to closed--loop during
synchronization, a slight hesitation in the spindles may be seen
when this switch occurs. This small deceleration may be more
apparent in systems with a smaller spindle motor or if
synchronization is done at higher speeds.
Program Restart, Mid--Start, and Interrupt Macros will be allowed.
If synchronization is disabled during an interrupt macro, it will
resynchronize upon return, in the event that all of the condition
checks listed in this section allow it to, otherwise a decode error
will result. Midstart and restart must also pass all conditions
described in this section.
17.5
Special Considerations for
Spindle Synchronization