Siemens SINUMERIK 840C - Manual (Page 1015)

12 Functional Descriptions 12.93
12.23 Actual-value system for workpiece
12.23 Actual-value system for workpiece
12.23.1 Corresponding data
• SD 5001 bit 0 (Actual-value system for workpiece)
• NC MD 5153 bit1 (Reset position 6th G group)
• NC MD 140* (Basic setting 6th G group)
• NC MD 142* (Basic setting of tool offset block)
• NC MD 548*, 550*, 552* (Address name)
The "Actual-value system for workpiece" function is a grinding function; it can, however, also
be used for other technologies.
General
The function is parameterized via setting and machine data. When the function is active, the
zero offsets (ZOs) selected in the program and the tool offset block (TO) are retained even af-
ter program end (M02/M30) or in the reset state. The variable basic setting of the ZOs (G54 -
G57) and the active TO (D number 1 - D819) after M02/M30 is meaningful only in an actual-
value system for workpieces.
12.23.2 Reference systems
It is possible to select between a machine-related and a workpiece-related actual-value display
for grinding processes.
In the machine-related actual-value system, no account is taken of any ZOs or TOs in the dis-
play of axis actual values. The displayed position values refer to the machine reference point
or to the control zero (see diagram, M corresponds to the machine reference point).
In contrast, when a ZO (G53 - G59) or TO (D0 - D819) is selected in a workpiece-related
actual-value system (designated as W1 or W2 in the diagram), the display immediately takes
account of offset and compensation values. With an active ZO (G54), the display for X and Y
changes from X = 500 to 250 (Pxw1) and Y = 100 to 250 (Pyw1).
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SINUMERIK 840C (IA)