Siemens sinumerik 840D sl Function Manual page 954

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: → 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 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.
Helical interpolation
The helical interpolation function is ideal for machining internal and external threads using
form milling cutters and for milling lubrication grooves.
The helix comprises two movements:
• Circular movement in one plane
• A linear movement perpendicular to this plane
High-level CNC language
The high-level language offers: → user-defined variables, → system variables, → macro
techniques.
High-speed digital inputs/outputs
The digital inputs can be used for example to start fast CNC program routines (interrupt
routines). The digital CNC outputs can be used to trigger fast, program-controlled switching
functions (SINUMERIK 840D).
HIGHSTEP
Summary of programming options for → PLCs of the AS300/AS400 system.
Special functions: Appendix
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Glossary
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