Detailed Description   
2.5 Workpiece-related actual-value system 
  Axis Types, Coordinate Systems, Frames (K2) 
2-118  Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0 
The actual values in the settable zero system (SZS) can be read from the part program for 
each axis using the variable $AA_IEN[axis]. 
The actual values in the basic zero system (BZS) can be read from the part program for 
each axis using the variable $AA_IBN[axis]. 
Actual-value display 
The programmed contour is always displayed in the WCS. 
The following offsets are added to the MCS: 
•  Kinematic transformation 
•  DRF offset/zero offset external 
•  Active frame 
•  Active tool offset of the current tool 
Switchover by PLC 
The actual values can be displayed in the WCS, SZS, BZS or MCS via the PLC. The PLC 
can define, which coordinate system corresponds to the workpiece coordinate system on a 
machine. 
On MMC poweron the MCS is preset.  
With the signal DB19 DBB0.7 "MCS/WCS switchover", it is also possible to switch from the 
PLC to the WCS. 
Transfer to PLC 
Depending on machine data  
MD20110 / MD20112, bit 1, 
the auxiliary functions (D, T, M) are output to the PLC (or not) on selection of the tool length 
compensation.  
 
 
Note 
If the WCS is selected from the PLC, an operator action can still be used to switch between 
the WCS and MCS for the relevant mode. 
However, when the mode and or area is changed, the WCS selected by the PLC is 
evaluated and activated. 
References: 
/FB1/ Description of Functions, Basic Machine; Mode Group, Channel, Program Operation, 
Reset Response (K1)