HEIDENHAIN iTNC 530 (60642x-03) ISO programming User Manual
Page 329

HEIDENHAIN iTNC 530
329
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.3 Miscellaneous functions f
o
r coor
dinat
e
data
Behavior with M92—Additional machine datum
If you want the coordinates in a positioning block to be based on the 
additional machine datum, end the block with M92.
Effect
M91 and M92 are effective only in the blocks in which they are 
programmed.
M91 and M92 take effect at the start of block.
Workpiece datum
If you want the coordinates to always be referenced to the machine 
datum, you can inhibit datum setting for one or more axes. 
If datum setting is inhibited for all axes, the TNC no longer displays the 
SET DATUM soft key in the Manual Operation mode.
The figure shows coordinate systems with the machine datum and 
workpiece datum.
M91/M92 in the Test Run mode
In order to be able to graphically simulate M91/M92 movements, you 
need to activate working space monitoring and display the workpiece 
blank referenced to the set datum (see "Showing the workpiece blank 
in the working space", page 585).
In addition to the machine datum, the machine tool builder 
can also define an additional machine-based position as a 
reference point.
For each axis, the machine tool builder defines the 
distance between the machine datum and this additional 
machine datum. Refer to the machine manual for more 
information.
Radius compensation remains the same in blocks that are 
programmed with M91 or M92. The tool length, however, 
is not compensated.
Z
X
Y
Z
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