Siemens sinumerik 840D sl Function Manual page 239

Switch ON/OFF
Coupled motion can be activated/deactivated via the part programs and synchronous
actions. In this context please ensure that the switch on and switch off is undertaken with the
same programming:
• Switch on: Part program → Switch off: Part program
• Switch on: Synchronous action → Switch off: Synchronous action
Synchronization on-the-fly
If switch on is performed while the leading axis is in motion, the coupled motion axis is first
accelerated to the velocity corresponding to the coupling. The position of the leading axis at
the time the velocities of the leading and coupled motion axes are synchronized then serves
as the start position for further coupled motion.
Operating modes
Coupled motion is effective in the AUTOMATIC, MDA and JOG modes.
Reference point approach
The following applies for referencing of axes of a coupled axis grouping:
• Leading axes
• Coupled motion axis: JOG/REF mode
• Coupled motion axis: Part program command G74
Special functions: Axis Couplings and ESR (M3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
When referencing the leading axis of a coupled axis grouping, the coupling to all coupled
motion axes is retained. The coupled motion axes move in synchronism with the leading
axis, as a function of their coupling factors.
When referencing a coupled motion axis of a coupled axis grouping, the coupling to the
leading axis is cancelled. If the coupling is canceled, the following alarm is displayed:
Alarm 16772 "Channel
coupling is opened."
The coupling is not activated again until JOG/REF mode is cancelled.
The display of this alarm can be suppressed using the following machine data:
MD11410 $MN_SUPPRESS_ALARM_MASK, Bit 29 = 1 (mask supporting special alarm
generation)
Caution
When the coupled motion axis is referenced, the coupling to the leading axis is cancelled.
If referencing is executed immediately with the leading axis, i.e. without changing
JOG/REF mode, the coupled motion axis does not traverse with the leading axis.
It is not possible to reference a coupled motion axis of a coupled axis grouping using the
G74 programming instruction.
Channel No. Block No.
block
Detailed description
2.1 Coupled motion
Axis No.
Axis is following axis,
19