Siemens SINUMERIK 840DE sl Function Manual page 275

General
The system variables to describe the elements of kinematic chains have the following
properties:
● The prefix for all of the system variables of the kinematic chain is $NT_, (N for NC, K for
transformation).
● The system variables can be read and written via NC programs.
● The system variables can be stored in archives and loaded to the NC again.
Data type
STRING
All system variables of the STRING data type have the following properties:
● Maximum string length: 31 characters
● No distinction is made between upper and lower case
Example: "Axis1" is identical to "AXIS1"
● Spaces and special characters are permitted
Example: "Axis1" is not identical to "Axis 1"
● Names that start with two underscores "__" are reserved for system purposes and must not
be used for user-defined names.
Note
Leading space
Since spaces are valid and distinct characters, names that start with a space followed by two
underscores "__" can, in principle, be used for user-defined names. However, because they
can be easily mistaken for system names, this procedure is not recommended.
Index_1
The individual elements are addressed via index_1. Index 0 is reversed, index 1 → 1. Element,
index 2 → 2. Element, ... (n+1) → (n+1) element, with n = ($MN_MM_NUM_KIN_TRAFOS - 1)
All system variables of an element have the same index.
Index_2
For system variables that contain a vector, the coordinates of the vector are addressed via
index_2.
● 0 → X axis
● 1 → Y axis
● 2 → Z axis
Transformations
Function Manual, 06/2019, A5E47435470B AA
K12 transformation definitions with kinematic chains
4.2 Commissioning
275