Positions In The Coordinate System - Siemens SINUMERIK 840D sl Function Manual

K2: Axis Types, Coordinate Systems, Frames
10.5 Frames
The machine data
$MC_MM_SYSTEM_DATAFRAME_MASK
can be used to configure data management frames for the system frames.
If you do not want a data management frame for a system frame, the frame does not have to
be saved. With G500, G54 to G599, the active frame is retained.
A separate data block _N_NC_UFR is used to archive global frames.
The block requested by the HMI is created if the machine data
MD18601 $MN_MM_NUM_GLOBAL_USER_FRAMES
or
MD18602 $MN_MM_NUM_GLOBAL_BASE_FRAMES
has a value greater than zero.
Channel-specific frames are saved in data block _N_CHANx_UFR.
In certain circumstances, alarms could be triggered when reintroducing saved data, if the frame
affiliates, be they NCU global or channel-specific, have been changed using machine data.
Data backup always takes place in accordance with the axis configuration set in the machine
data, not in accordance with the currently valid geometry axis assignment.
10.5.11

Positions in the coordinate system

The setpoint positions in the coordinate system can be read via the following system variables.
The actual values can be displayed in the WCS, SZS, BZS or MCS via the PLC. There is a
softkey for actual-value display in MCS/WCS. Machine manufacturers can define on the PLC
side, which coordinate system corresponds to the workpiece coordinate system on their
machines. The HMI requests the appropriate actual values from the NCK.
$AA_IM[axis]
The setpoints in the machine coordinate system can be read for each axis using the variables
$AA_IM[axis].
$AA_IEN[axis]
The setpoints in the settable zero system (SZS) can be read for each axis using the variables
$AA_IEN[axis].
$AA_IBN[axis]
The setpoints in the basic zero system (BZS) can be read using the variable $AA_IBN[axis].
$AA_IW[axis]
The setpoints in the workpiece coordinate system (WCS) can be read using the variable
$AA_IW[axis].
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Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions