Programming A Lead Link Axis - Siemens SINUMERIK 840D sl Function Manual

B3: Several operator panels connected to several NCUs, distributed systems - only 840D sl
2.11 Lead link axis
2.11.1

Programming a lead link axis

Master value axis view
Only the NCU which is physically assigned to the master value axis can program travel
motions for this axis. The travel program must not contain any special functions or
operations. The configuration summarized in the preceding sections allows the control to
perform the required setpoint delay automatically so that the leading axis and following axes
are interpolated synchronously on the other NCUs.
Following axes view
The programming on the NCU of the following axes must not contain motion commands for
the leading value axis (master value axis). Any violation of this rule triggers an alarm.
The leading value axis is addressed in the usual manner via the channel axis identifier. The
states of the leading value axis can be accessed via special system variables.
System variables
The following system variables can be used in conjunction with the channel axis identifier of
the master value axis:
$AA_LEAD_SP; Simulated master value position
SAA_LEAD_SV; Simulated master value velocity
If these system variables are updated by the home NCU of the master axis, the new values
are also transferred to any other NCUs which wish to control slave axes as a function of this
master axis.
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Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Extended Functions