Siemens SINUMERIK 840D sl Function Manual page 620

TE3: Speed/torque coupling, master-slave
16.7 Response on activation/deactivation
– MD37272 $MA_MS_VELO_TOL_FINE ("Tolerance fine").
Figure 16-6
Switch off without braking
If the coupling is switched off with the MASLOF program command, the coupling will be switched
off immediately for spindles in speed control mode. The slave spindles maintain their speeds
at the time that the coupling is switched off until a new speed is programmed.
620
Note
The "Speed tolerance coarse" signal can be used to implement a monitoring function
on the PLC side that checks a coupled master-slave grouping for loss of speed
synchronism.
The "Speed tolerance fine" signal can be used to directly derive the time taken to close
the coupling mechanically and switch on the torque equalization controller.
Coupling operation at different speeds
Function Manual, 01/2015, 6FC5397-2BP40-5BA2
Special functions