Siemens SINUMERIK 840Di sl Programming Manual page 547

Tool radius compensation
To directly program a desired → workpiece contour, the control must traverse an equidistant
path to the programmed contour taking into account the radius of the tool that is being used
(G41/G42).
Transformation
Additive or absolute work offset of an axis.
Traversing 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 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 modules: 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.
Variable definition
A variable definition includes the specification of a data type and a variable name. The
variable names can be used to access the value of the variables.
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
Glossary
547