Siemens SINUMERIK 840D sl Function Manual page 1105

Fast retraction from contour
When an interrupt occurs, a motion can be initiated via the CNC machining program,
enabling the tool to be quickly retracted from the workpiece contour that is currently being
machined. The retraction angle and the distance retracted can also be parameterized. After
fast retraction, an interrupt routine can also be executed (SINUMERIK 840D).
Feed override
The programmed velocity is overriden by the current velocity setting made via the → machine
control panel or from the → PLC (0 to 200%). The feedrate can also be corrected by a
programmable percentage factor (1-200%) in the machining program.
Finished-part contour
Contour of the finished workpiece. See → Raw part.
Fixed machine point
Point that is uniquely defined by the machine tool, e.g. machine reference point.
Fixed-point approach
Machine tools can approach fixed points such as a tool change point, loading point, pallet
change point, etc. in a defined way. The coordinates of these points are stored in the control.
The control moves the relevant axes in → rapid traverse, whenever possible.
Frame
A frame is an arithmetic rule that transforms one Cartesian coordinate system into another
Cartesian coordinate system. A frame contains the following components: → zero offset,
→ rotation, → scaling, → mirroring.
Geometry
Description of a → workpiece in the → workpiece coordinate system.
Geometry axis
Geometry axes are used to describe a 2- or 3-dimensional area in the workpiece coordinate
system.
Ground
Ground is taken as the total of all linked inactive parts of a device which will not become live
with a dangerous contact voltage even in the event of a malfunction.
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
Glossary
1105