Siemens SINUMERIK 840D sl Programming Manual page 69

Tool geometry variables (length, radius)
The tool geometry variables consist of several components (geometry, wear). The control
computes the components to a certain dimension (e.g. overall length 1, total radius). The
respective overall dimension becomes effective when the compensation memory is activated.
How these values are calculated in the axes is determined by the tool type and the current
plane (G17/G18/G19).
References
Function Manual, Basic Functions; Tool Offsets (W1); Section "Tool edge"
Fundamentals
Programming Manual, 09/2011, 6FC5398-1BP40-2BA0
Tool offsets
5.4 Tool compensation memory
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