Siemens Sinumerik 840D sl Programming Manual page 536

Glossary
Synchronized actions
1. Auxiliary function output
During workpiece machining, technological functions (→ auxiliary functions) can be output
from the CNC program to the PLC. For example, these auxiliary functions are used to
control additional equipment for the machine tool, such as quills, grabbers, clamping
chucks, etc.
2. Fast auxiliary function output
For time-critical switching functions, the acknowledgement times for the → auxiliary
functions can be minimized and unnecessary hold points in the machining process can be
avoided.
Synchronized axes
Synchronized axes take the same time to traverse their path as the geometry axes take for
their path.
Synchronized axis
A synchronized axis is the → gantry axis whose set position is continuously derived from the
motion of the → leading axis and is, thus, moved synchronously with the leading axis. From
the point of view of the programmer and operator, the synchronized axis "does not exist".
System memory
The system memory is a memory in the CPU in which the following data is stored:
● Data required by the operating system
● The operands timers, counters, markers
System variable
A variable that exists without any input from the programmer of a → part program. It is defined
by a data type and the variable name preceded by the character $. See → User-defined variable.
Tapping without compensating chuck
This function allows threads to be tapped without a compensating chuck. By using the
interpolating method of the spindle as a rotary axis and the drilling axis, threads can be cut to
a precise final drilling depth, e.g. for blind hole threads (requirement: spindles in axis operation).
Text editor
See → Editor
TOA area
The TOA area includes all tool and magazine data. By default, this area coincides with the
→ channel area with regard to the access of the data. However, machine data can be used to
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Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Fundamentals