Siemens sinumerik 840D sl Function Manual page 616

Different motor speeds
The master and slave axis can have different gear reduction ratios between the motors and
the mechanical coupling. With these types of axes, the master and slave rotate at different
speeds. When the coupling is active, the same load speed is standardized internally so that
different motor speeds are possible for the master and slave without having to set further
machine data.
Speed feedforward control
If speed feedforward control is active in the master axis, speed feedforward control must also
be activated in the slave axis. Non-active speed feedforward control in the slave axis causes
a "Contour monitoring" alarm in the slave axis.
Computing time load
Each master-slave coupling places a load on the position control level and the interpolation
level. The table shows the computing time required depending on the NCU hardware.
NCU
572
573
Configuration alarms
During power ON of the control, the configuration machine data are checked and alarms set
as necessary:
If the master and slave axes are identical for speed coupling, the alarm "75150 Slave axis
AX1 and master axis are identical for speed setpoint coupling" is present after POWER ON.
If the master axis and slave axis are identical for torque control, alarm "75151 Slave axis
AX1 and master axis identical for torque controller" is present.
All axes of the mode group follow on; the alarms can only be reset with POWER ON.
2.2.4 Torque controller
The torque controller between master and slave ensures even torque distribution between
the master and slave axis. The input variable of the controller is the torque difference Mdiff
between the master and slave axis; the output is a setpoint speed nset, which is applied to
the master and slave axes.
The controller consists of a P component and an I component. Both parts must be
parameterized separately.
The machine data of the slave axis is always relevant for the configuration of the particular
master-slave torque control.
Special functions: Speed/Torque Coupling, Master-Slave (TE3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Position control
1. Coupling 0.120 ms
Each addtional coupling +0.050 ms
1. Coupling 0.040 ms
Each addtional coupling +0.020 ms
Detailed description
2.2 Speed/torque coupling (up to SW 5.x)
Interpolator level
1. Coupling 0.100 ms
Each addtional coupling +0.020 ms
1. Coupling 0.030 ms
Each addtional coupling +0.010 ms
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