Automatic Synchronization - Siemens SINUMERIK 840D sl Function Manual

Selecting the reference point
To ensure that the shortest possible paths are traversed when the gantry axes are
referenced, the reference point values from leading and synchronous axes should be the
same in the machine data:
MD34100 $MA_REFP_SET_POS (reference point value/destination point for distance­coded
system)
Allowance for deviations in distance between the zero mark and the reference point must be
made for specific axes via the machine data:
MD34080 $MA_REFP_MOVE_DIST (reference point distance)
MD34090 $MA_REFP_MOVE_DIST_CORR (reference point offset/absolute offset)
Referencing direction selection
The zero mark search direction of the synchronous axis can be defined via the machine data:
MD37150 $MA_GANTRY_FUNCTION_MASK, Bit 1
Bit
1
During referencing, the reference point value of the leading axis is specified as the target
position for all axes in the grouping for the synchronization compensatory motion. This
position is then approached without axis coupling. The absolute encoders and distanced-
coded encoders of the leading axis will be set to the current actual position of the leading axis
or to the reference point by the following machine data:
MD34330 $MA_REFP_STOP_AT_ABS_MARKER (Distance­coded linear measuring system
without destination point)
If only one reference cam is used for the leading and synchronous axes, then this must be
taken into account in the PLC user program.
2.3.2

Automatic synchronization

Automatic synchronization can take place:
• in referencing mode (see Section "Detailed description", "Introduction")
• in other modes, as described in the following.
If a gantry grouping is switched to follow-up mode, monitoring of the actual values between
the leading and synchronized axes is disabled. The grouping is no longer synchronized as a
result. Independent of axes positions, the following interface signal will be set to 0 (from
leading axis)
DB31, ... DBX101.5 (gantry grouping is synchronous)
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
Value Meaning
0 Zero mark search direction of the synchronous axis analog to machine data:
MD34010 $MA_REFP_CAM_DIR_IS_MINUS
1 Zero mark search direction of the synchronous axis the same as the leading axis
2.3 Referencing and synchronization of gantry axes
G1: Gantry axes
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