Constraints - Siemens SINUMERIK 840D sl Function Manual

M1: Kinematic transformation
7.8 Activating transformation machine data via parts program/softkey
7.8.2

Constraints

Change machine data
The machine data which affect an active transformation may not be altered; any attempt to
do so will generate an alarm.
These are generally all machine data assigned to a transformation via the associated
transformation data group. Machine data that are included in the group of an active
transformation, but not in use, can be altered (although this would hardly be meaningful). For
example, it would be possible to change machine data MD24564
$MC_TRAFO5_NUTATOR_AX_ANGLE_n for an active transformation with MD24100
$MC_$MC_TRAFO_TYPE = 16 (5-axis transformation with rotatable tool and two mutually
perpendicular rotary axes A and B) since this particular machine data is not involved in the
transformation.
Please note that machine data MD21110 $MC_X_AXIS_IN_OLD_X_Z_PLANE may not be
altered for an active orientation transformation.
Note
In the case of a program interruption (Repos, deletion of distance to go, ASUBs, etc.), the
control system requires a number of different blocks that have already been executed for the
repositioning operation. The rule forbidding the machine data of an active transformation to
be altered also refers to these blocks.
Example:
Two orientation transformations are set via machine data, e.g. MD24100
$MC_TRAFO_TYPE_1 = 16, MD24200 $MC_TRAFO_TYPE_2 = 18.
Assume that the second transformation is active when the NEWCONFIG command is
executed. In this case, all machine data that relate only to the first transformation may be
changed, e.g.:
MD24500 $MC_TRAFO5_PART_OFFSET_1
but not, for instance:
MD24650 $MC_TRAFO5_BASE_TOOL_2
or
MD21110 $MC_X_AXIS_IN_OLD_X_Z_PLANE
Furthermore, another transformation (TRANSMIT) can be set, for example with MD24300
$MC_TRAFO_TYPE_3 = 256 and can be parameterized with additional machine data.
Defining geometry axes
Geometry axes must be defined before starting the control system with the following
machine data:
MD24120 $MC_TRAFO_GEOAX_ASSIGN_TAB_X[n]
or
MD20050 $MC_AXCONF_GEOAX_ASSIGN_TAB[n]
578
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Extended Functions