Tool Offset Functions; Tool Offset Data Memory; Tool Length Compensation (G43, G44, G49) - Siemens Sinumerik 840D sl Programming Manual

Motion commands

3.4 Tool offset functions

3.4 Tool offset functions
3.4.1

Tool offset data memory

The Siemens tool data memory must be used, as programs in the Siemens Mode and in the
ISO Direct Mode must run alternately on the control system. Hence, length, geometry and
wear exists in each tool offset data memory. In the Siemens mode, the offset data memory is
addressed with "T" (Tool No.) and "D" (cutting edge no.). abbreviated as T/D No.
In programs that are written in ISO dialect, the tool offset no. is addressed with "D" (radius)
or H (length), denoted hereafter as D/H No.
For unique assignment between D and H numbers or the T/D number, one must add the
$TC_DPH[t,d] element to the tool data offset memory. The D/H number is input in ISO
dialect in this element.
Table 3- 7
T
1
1
1
2
2
2
For an assignment of tool length compensations of the geometry axes that is independent of
the plane selection, the setting data $SC_TOOL_LENGTH_CONST must contain the value
"17". Length 1 is always assigned to the Z axis in this case.
3.4.2

Tool length compensation (G43, G44, G49)

In tool length compensation, the amount of the specified values in the program stored in the
tool offset data memory is added to the Z axis or subtracted from it to undertake a offset of
the programmed paths according to the length of the cutting tool.
Commands
While executing the tool length compensation, the addition or subtraction of the tool offset
data is determined through the used G function and the direction of offset is determined with
the H functions.
54
Example: Set tool offset data
D/cutting edge
1
2
3
1
2
3
ISO_H Radius
$TC_DPH
10
11
12
13
14
15
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
Length
ISO Milling