Siemens SINUMERIK 840Di sl Programming Manual page 353

Changing the offset number D
The offset number D can be changed in compensation mode.
A modified tool radius is active with effect from the block, in which the new D number is
programmed.
Caution
The radius change or compensation movement is performed across the entire block and only
reaches the new equidistance at the programmed end point.
With linear movements, the tool travels along an inclined path between the starting point and
end point; with circular interpolation spiral movements are produced.
Changing the tool radius
This can be achieved, for example, using system variables. The execution is the same as for
changes in the D number.
Caution
The modified values only take effect the next time T or D is programmed. The change only
applies with effect from the next block.
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
8.8 Tool radius compensation (G40, G41, G42)
Tool offsets
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