Siemens Sinumerik 840D sl Programming Manual page 209

Subprogram
A sequence of instructions of a -> part program which can be called multiple times with
various output parameters. Subprograms are always called from the main programs.
Subprograms can be locked to prevent unauthorized export and impermissible viewing. ->
Cycles are subprograms from the perspective of type.
Synchronization
Instructions in -> part programs for coordinating working cycles in different -> channels at
certain machining points.
Synchronized actions
● Auxiliary function output
● Fast auxiliary function output
Synchronized actions can be combined to build programs (technology cycles). Axis
programs can be started in the same IPO cycle, e.g. by scanning digital inputs.
Synchronized axes
Synchronized axes require the same time to traverse the path as -> geometry axes.
Synchronous spindle
Accurate synchronism of angle between a master spindle and one or more slave spindles.
This way, the flying transfer of a workpiece from Spindle 1 to Spindle 2 is possible in turning
machines.
In addition to speed synchronism, relative angle positions of the spindles can also be
programmed, e.g. "floating" or the position-oriented transfer of inclined workpieces.
Several pairs of synchronous spindles can be implemented.
System variables
A variable that exists even though it was not programmed by -> part program programmers.
It is defined by the data type and the variable name with the sign $. See also -> User-defined
variable.
ISO Milling
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
Technological functions ( -> auxiliary functions) can be output by the CNC program to the
PLC during the machining of a workpiece. These auxiliary functions can, for instance, be
used to control ancillary equipment on the machine (quill, gripper, chuck etc.).
The acknowledgement times of -> auxiliary functions can be reduced and unnecessary
machining process for executing less critical switching functions can be avoided.
Glossary
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