Siemens SINUMERIK 840D sl Function Manual page 164

G1: Gantry axes
2.4 Start-up of gantry axes
Check of dynamic response adaptation:
The following errors of the leading and synchronized axes must be equal in magnitude when
the axes are operating at the same speed!
For the purpose of fine tuning, it may be necessary to adjustservo gain factors or feedforward
control parameters slightly to achieve an optimum result.
Referencing gantry axes
The positions of the reference points of the leading and synchronized axes must first be set to
almost identical values.
To ensure that the synchronization compensatory motion of the gantry axes is not started
automatically, the gantry warning limit must be set to 0 at the first start-up before referencing:
MD37100 $MA_GANTRY_POS_TOL (gantry axis definition)
This will prevent a warning message being output during traversing motion.
In cases where an excessively high additional torque is acting on the drives due to
misalignment between the leading and synchronized axes, the gantry grouping must be
aligned before the axes are traversed. After this, gantry axes referencing must be performed
according to the Section "Referencing and synchronizing of gantry axes" and:
References:
Function Manual Basic Functions; Reference Point Travel (R1)
After the leading and synchronized axes have been referenced, the difference between them
must be measured (comparison of position actual value indication in "Service axes" display of
"Diagnosis" operating area). This difference must be applied as the reference point offset:
MD34080 $MA_REFP_MOVE_DIST (reference point distance)
MD34090 $MA_REFP_MOVE_DIST_CORR (reference point offset/absolute offset)
The differences in distance between the zero mark and reference point must also be
calculated for each gantry axis and adjusted. They are to be customized, via the following
machine data, in such a way that the position actual values of the leading and synchronized
axes are identical after execution of the compensatory motion:
MD34080 $MA_REFP_MOVE_DIST (reference point distance)
MD34090 $MA_REFP_MOVE_DIST_CORR (reference point offset/absolute offset)
Synchronizing gantry axes
The gantry synchronization process must be activated with IS "Start gantry synchronization"
(see Section "Referencing and synchronizing of gantry axes"). Once the axes have been
synchronized (IS "Gantry grouping is synchronized" = 1), the dimensional offset between the
leading and synchronized axes must be checked to ensure that it equals 0. Corrections may
need to be made in the machine data mentioned above.
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Function Manual, 09/2011, 6FC5397-2BP40-2BA0
Special Functions