Siemens Sinumerik 840D sl Programming Manual page 533

Description
Master value coupling requires synchronization of the leading and the following axes. This
synchronization can only be achieved if the following axis is inside the tolerance range of the
curve definition calculated from the curve table when the master value coupling is activated.
The tolerance range for the position of the following axis is defined via machine data MD
37200: COUPLE_POS_POL_COARSE A_LEAD_TYPE.
If the following axis is not yet at the correct position when the master value coupling is
activated, the synchronization run is automatically initiated as soon as the position setpoint
value calculated for the following axis is approximately the real following axis position. During
the synchronization procedure the following axis is traversed in the direction that is defined by
the 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.
Job planning
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
9.3 Axial leading value coupling (LEADON, LEADOF)
Axis couplings
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