Siemens SINUMERIK 840D sl Function Manual page 853

specify that multiple channels share one → TOA unit so that common tool management data
is then available to these channels.
TOA unit
Each → TOA area can have more than one TOA unit. The number of possible TOA units is
limited by the maximum number of active → channels. A TOA unit includes exactly one tool
data block and one magazine data block. In addition, a TOA unit can also contain a toolholder
data block (optional).
Tool
Active part on the machine tool that implements machining (e.g. turning tool, milling tool, drill,
LASER beam, etc.).
Tool nose radius compensation
Contour programming assumes that the tool is pointed. Because this is not actually the case
in practice, the curvature radius of the tool used must be communicated to the controller which
then takes it into account. The curvature center is maintained equidistantly around the contour,
offset by the curvature radius.
Tool offset
Consideration of the tool dimensions in calculating the path.
Tool radius compensation
To directly program a desired → workpiece contour, the control must traverse an equistant path
to the programmed contour taking into account the radius of the tool that is being used (G41/
G42).
Transformation
Additive or absolute zero offset of an axis.
Travel range
The maximum permissible travel range for linear axes is ± 9 decades. The absolute value
depends on the selected input and position control resolution and the unit of measurement
(inch or metric).
User interface
The user interface (UI) is the display medium for a CNC in the form of a screen. It features
horizontal and vertical softkeys.
Special functions
Function Manual, 01/2015, 6FC5397-2BP40-5BA2
Glossary
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