Siemens SINUMERIK 840D sl Programming Manual page 915

setpoint speed of the following axis (calculated from master spindle and using the CTAB curve
table).
No synchronism
If the following axis position calculated moves away from the current following axis position
when the master value coupling is activated, it is not possible to establish synchronization.
Actual value and setpoint coupling
Setpoint coupling provides better synchronization of the leading and following axis than actual
value coupling and is therefore set by default.
Setpoint coupling is only possible if the leading and following axis are interpolated by the same
NCU. With an external leading axis, the following axis can only be coupled to the leading axis
via the actual values.
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
Y
Following axis position
NCU
Setpoint value coupling
Ax1
Actual value coupling
Y
Ax2
Work preparation
3.16 Axis couplings
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