Siemens SINUMERIK 840D sl Function Manual page 908

Synchronous Spindles (S3)
Brief description
Read current angular offset
Using axial system variables, it is possible to read the current position offset between the FS
and LS in the NC part program. The following two position offsets exist:
● Current position offset of setpoint between FS and LS
● Current position offset of actual value between FS and LS
(Explanation of <axis identifier>, see section "Synchronous operation")
Activation after power ON
Synchronous mode can also be activated with non-referenced/synchronized FS or LS (IS
"Referenced/synchronized 1 or 2" DB31, ... DBX60.4 or DBX60.5 = 0). In this case, a
warning message is displayed.
Example:
LS and FS are already coupled in a friction lock via a workpiece after power ON.
14.1.6 Deselecting the part program's synchronous mode
Deactivate coupling COUPOF, COUPOFS
Synchronous mode between the specified spindles is canceled by the part program
instruction COUPOF. Three variants are possible.
If synchronous mode is canceled between the specified spindles using COUPOF, then it is
irrelevant whether this coupling is permanently configured or user defined. The leading and
following spindles can be at standstill or in motion when synchronous operation is
deactivated.
On switching off the synchronous mode with COUPOF, the following spindle is put into control
mode. The originally programmed S-word is no longer valid for the FS, the following spindle
can be operated like any other normal spindle.
When the coupling is deactivated with COUPOF, a block preprocessing stop STOPRE is
generally initiated internally in the control.
The COUPOFS instruction can be used to deactivate a coupling either as quickly as possible
with a stop and no position details or with a stop at the programmed position.
908
$AA_COUP_OFFS [<axis identifier for FS>]
$VA_COUP_OFFS [<axis identifier for FS>]
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Extended Functions