Siemens SINUMERIK 840DE Programming Manual page 499

then takes it into account. The curvature center is maintained equidistantly around the
contour offset by the radius of curvature.
Tool offset
By programming a T function (5 integer decades) in the block, you can select the tool. Up to
9 cutting edges (D addresses) can be assigned to every T number. The number of tools to
be managed in the controller is specified in the configuring data.
Tool radius compensation
In order to be able to program a desired -> workpiece contour directly, the control must
traverse a path equidistant to the programmed contour, taking into account the radius of the
tool used (G41/G42).
Transformation
Programming in a Cartesian coordinate system, execution in a non-Cartesian coordinate
system (e.g., with machine axes as rotary axes).
Traversing range
The maximum permissible traversing range on linear axes is ± 9 decades. The absolute
value depends on the selected input sensitivity and positioning resolution and the system of
units used (inches or metric).
User interface
The user interface (UI) is the display medium for a CNC control in the form of a screen. It is
laid out with horizontal and vertical softkeys.
User memory
All program and data, such as part programs, subroutines, comments, tool compensations,
and work offsets/frames, as well as channel- and program user data can be stored in the
shared CNC user memory.
User program
User programs for the S7-300 automation systems are created using the programming
language STEP 7. The user program has a modular layout and consists of individual blocks.
The basic block types are:
Code blocks: These blocks contain the STEP 7 commands.
Data blocks: These blocks contain the constants and variables for the STEP 7 program.
User-defined variable
The user can declare user-defined variables for any use in the -> parts program or data
block (global user data). A definition contains a data type specification and the variable
name. See -> system variable.
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
Glossary
Glossary-23