Siemens SINUMERIK 840Di Function Manual page 2031

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 feed velocity can also be offset by applying
a programmable percentage factor (1 to 200%) in the machining program.
Finished-part contour
Contour of the finished workpiece. See → Raw part.
Fixed-point approach
Machine tools can approach fixed points such as the tool change point, loading point, pallet
change point, etc., in a defined manner. The coordinates of these points are stored in the
control. The control moves the relevant axes in → rapid traverse, whenever possible.
Frame
A frame represents a calculation rule that transfers one Cartesian coordinates sytem to
another Cartesian coordinate system. A frame contains the following components: → work
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 refers to all connected, inactive parts of equipment that cannot assume dangerous
touch voltage even in the event of a fault.
Helical interpolation
Helical interpolation is especially suitable for easy machining inside or outside threads with
form cutters and for milling lubricating grooves.
The helix consists of two motions:
• A circular movement in one plane
• A linear movement perpendicular to this plane
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Glossary
Glossary-7