Siemens sinumerik 840D sl Function Manual page 243

2.1.3 Effectiveness of PLC interface signals
Independent coupled motion axis
All the associated channel and axis specific interface signals of the coupled-motion axis are
effective for the independent motion of a coupled-motion axis, e.g.:
• DB21, ... DBX0.3 (Activate DRF)
• DB31, ... DBX0.0 - 0.7 (feed offset)
• DB31, ... DBX1.3 (axis blocking)
• DB31, ... DBX2.1 (control system enable)
• DB31, ... DBX4.0 - 4.2 (activate handwheel)
• DB31, ... DBX4.3 (feed stop)
• ...
This allows the speed to be changed for the independent motion of a coupled motion axis
using a feed override or a DRF offset to be defined using the handwheel in AUTOMATIC and
MDA modes.
Dependent coupled motion axis
With respect to the motion of a coupled motion axis, which is dependent on the leading axis,
only the coupled-motion axis interface signals that effect termination of the motion (e.g. axis-
specific feed stop, axis inhibit, control system enable, etc.) are effective.
Leading axis
When a coupled axis grouping is active, the interface signals (IS) of the leading axis are
applied to the appropriate coupled motion axis via the axis coupling, i.e.
• A position offset or feed control action of the leading axis is applied via the coupling factor
• Shutdown of the leading axis as the result of an interface signal (e.g. axis-specific feed
Position measuring system 1/2 (DB31, ... DBX1.5/1.6))
Switch-over of the position measuring system for the leading and coupled motion axes is not
inhibited for an active coupled axis grouping. The coupling is not canceled.
Recommendation: Switch-over the measuring system when the coupling is deactivated.
Special functions: Axis Couplings and ESR (M3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
to effect an appropriate position offset or feed control action in the coupled motion axis.
stop, axis inhibit, servo enable, etc.) causes the corresponding coupled motion axis to
shut down.
Detailed description
2.1 Coupled motion
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