Absolute Workpiece Positions; Incremental Workpiece Positions - HEIDENHAIN POSITIP 880 User Manual

Absolute Workpiece Positions

Each position on the workpiece is uniquely identified by its absolute
coordinates. See Fig. I.6.
Example: Absolute coordinates of position 1:
X = 20 mm
Y = 10 mm
Z = 15 mm
If you are drilling or milling a workpiece according to a workpiece
drawing with absolute coordinates, you are moving the tool to the
value of the coordinates.

Incremental Workpiece Positions

A position can also be referenced to the preceding nominal position.
In this case the relative datum is always the last nominal position.
Such coordinates are referred to as incremental coordinates
(increment = increase). They are also called incremental or chain
dimensions (since the positions are defined as a chain of dimensions).
Incremental coordinates are designated with the prefix I.
Example: Incremental coordinates of position
2. See Fig. I.7
Absolute coordinates of position 2:
X = 10 mm
Y = 5 mm
Z = 20 mm
Incremental coordinates of position 3:
IX = 10 mm
IY = 10 mm
IZ = –15 mm
If you are drilling or milling a workpiece according to a drawing with
incremental coordinates, you are moving the tool by the value of the
coordinates.
POSITIP 880
Fig. I.6
3 referenced to position
Fig. I.7
Position 1 definition through absolute
coordinates
Positions 2 and 3 through incremental
coordinates
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