Siemens SINUMERIK 840D sl Function Manual page 913

14.1.8 Monitoring of synchronous operation
Fine/coarse synchronism
In addition to conventional spindle monitoring operations, synchronous operation between
the FS and LS is also monitored in synchronous mode.
For this, IS "Synchronism fine" (DB31, ... DBX98.0) or IS "Synchronism coarse" (DB31, ...
DBX98.1) is transmitted to the PLC to indicate whether the current position (AV, DV) or
actual speed (VV) of the following spindle is within the specified tolerance window.
When the coupling is switched on, the signals "Coarse synchronism" and "Fine synchronism"
are updated when setpoint synchronism is reached.
The size of the tolerance windows is set with machine data of the FS. Reaching of the
synchronism is influenced by the following factors:
● AV, DV: Position variance between FS and LS
● VV: Difference in speed between FS and LS
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Synchronous Spindles (S3)
Brief description
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