Siemens SINUMERIK 840D sl Function Manual page 781

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 times, counters, markers
System variables
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 reach of the data. However, machine data can be used to
specify that multiple channels share one → TOA unit so that common tool management data
is then available to these channels.
TOA unit
Each → TOA area can have more than one TOA unit. The number of possible TOA units is
limited by the maximum number of active → channels. A TOA unit includes exactly one tool
data block and one magazine data block. In addition, a TOA unit can also contain a toolholder
data block (optional).
Tool
Active part on the machine tool that implements machining (e.g. turning tool, milling tool, drill,
LASER beam, etc.).
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
Glossary
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