Siemens sinumerik 840D sl Function Manual page 596

2.1.2 Coupling diagram
If the coupling is closed, the slave axis is traversed only with the load-side setpoint speed of
the master axis. It is therefore only speed-controlled, not position-controlled.
No positional deviation control is implemented between master and slave axes. A torque
compensatory controller divides the torque evenly over the master and slave axes.
An additional torque can be used to achieve a tension between the master and slave axis.
If different motors are used, individual weighting factors can be used to adapt the torque
distribution.
Figure 2-4 Control structure
Special functions: Speed/Torque Coupling, Master-Slave (TE3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
2.1 Speed/torque coupling, master-slave (SW 6 and higher)
Detailed description
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