Siemens SINUMERIK 840D sl Function Manual page 703

Note
Owing to the grouping of cam pairs (eight in each group), it is possible to assign different
access authorization levels (e.g. for machine-related and workpiece-related cam positions).
The positions are entered in the machine coordinate system. No check is made with respect
to the maximum traversing range.
Dimension system metric/inch
MD10260 CONVERT_SCALING_SYSTEM=1
With the above machine data setting, the cam positions no longer refer to the basic system,
but to the system configured in machine data:
MD10270 POS_TAB_SCALING_SYSTEM
MD10270 POS_TAB_SCALING_SYSTEM=0:
MD10270 POS_TAB_SCALING_SYSTEM=1:
MD10270 POS_TAB_SCALING_SYSTEM
The above machine data therefore defines the dimension system for position parameters
from setting data:
SD41500 to SD41507
A switchover with G70/G71 or G700/G710 has no effect.
Sensing of cam positions
To set the cam signals, the actual position of the axes is compared to the cam position.
Writing/reading of cam positions
The setting data can be read and written via HMI, PLC and part program.
Accesses from the part program are not synchronous to machining.
Synchronization can only be achieved by means of a programmed block preprocessing stop
(STOPRE command).
It is possible to read and write the cam positions with FB2 and FB3 in the PLC user program.
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
N3: Software cams, position switching cycles - only 840D sl
Metric
inch
9.2 Cam signals and cam positions
703