Siemens sinumerik 840D sl Function Manual page 279

2.3.4 Effectiveness of PLC interface signals
Leading axis
When a coupled axis group is active, the interface signals (IS) of the leading axis are applied
to the appropriate following axis via axis coupling. i.e.:
• a feed control action of the leading axis is applied via the master value coupling to effect
• shutdown of the leading axis as the result of an IS (e.g. axis-specific feed stop, axis
Position measuring system 1/2 (DB31, ... DBX1.5/1.6))
Switch-over of the position measuring system for the leading and following axes is not
inhibited for an active coupled axis group. The coupling is not canceled.
Recommendation: Switch the measuring system over when the coupling is deactivated.
2.3.5 Special characteristics of the axis master value coupling function
Control system dynamics
Depending on the application in question, it may be advisable to match the position controller
parameter settings (e.g. servo gain factor) of the leading axis and following axis in an axis
grouping. It may be necessary to activate other parameter sets for the following axis. The
dynamics of the following axis should be the same or better than those of the leading axis.
Status of coupling
see Chapter "Coupled Motion", "Special Features of the Function"
Actual value display
The display of the actual value is updated for all axes of in a master value coupled axis
grouping (only real axes) coupled via a master value.
Interpolation
When the movement defined in the curve table is interpolated, axis position and axis speed
are calculated for a master value and its speed.
Logging
The curve tables generated by the definition of motion sequences are stored in the battery-
backed memory.
The curve tables are not lost when the control system is switched off.
Special functions: Axis Couplings and ESR (M3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
an appropriate feed control action in the following axis.
inhibit, servo enable, etc.) causes the corresponding coupled motion axis to shut down.
Detailed description
2.3 Master value coupling
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