Siemens SINUMERIK 840D sl Function Manual page 149

Extended monitoring of the synchronism difference
An extended monitoring of the synchronism difference can be activated using the following
machine data:
MD37150 $MA_GANTRY_FUNCTION_MASK, Bit 0 = 1
For the extended monitoring, a synchronism difference between the leading and synchronous
axis, obtained when tracking or when the gantry grouping is opened, is taken into account.
The extended monitoring becomes active after the NC boots after the first referencing
(incremental encoder) or synchronization (absolute encoder).
Exceeding the gantry trip limit
If, when the extended monitoring is active, the trip limit of the synchronism difference is
exceeded, Alarm 10653 "Error limit exceeded" is displayed.
In order to be able to reset the alarm, proceed as follows:
1. Deactivating extended monitoring:
MD37150 $MA_GANTRY_FUNCTION_MASK, Bit 0 = 0
2. Deleting the synchronism difference displayed in the machine data:
MD37135 $GANTRY_ACT_POS_TOL_ERROR = 0
3. Cancel alarm
4. Re-reference or re-synchronize the axes of the gantry grouping
5. Reactivating extended monitoring:
MD37150 $MA_GANTRY_FUNCTION_MASK, Bit 0 = 1
Referencing and synchronization of gantry axes
In cases where an incremental measuring system is being used for the leading or the
synchronous axis, after the NC boots, the measuring systems must be referenced,
maintaining the axis coupling.
After every axis in the gantry grouping has approached its reference point, any misalignment
that may exist between the axes must be eliminated (gantry synchronization process). Once
this has been performed, the NC/PLC interface signal is set:
DB31, ... DBX101.5 == 1 (gantry grouping is synchronized)
For the sequence when referencing or synchronizing gantry axes, see Chapter Referencing
and synchronization of gantry axes [Page 151].
Control system dynamics
From the user perspective, a gantry grouping is exclusively traversed via the leading axis.
The NC generates the setpoints of the synchronous axes directly from the setpoints of the
leading axis in time synchronism and outputs these to them. To minimize the synchronism
differences, the dynamic control response settings of all of the axes of a gantry grouping must
be identical (see Chapter "Start-up of gantry axes [Page 161]").
Note
Identical control dynamics must be set for all axes of a gantry grouping.
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
G1: Gantry axes
2.2 "Gantry axes" function
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