Siemens SINUMERIK 840D sl Function Manual page 1092

Glossary
Drive
The drive is the unit of the CNC that performs the speed and torque control based on the
settings of the NC.
Dynamic feedforward control
Inaccuracies in the → contour due to following errors can be practically eliminated using
dynamic, acceleration-dependent feedforward control. This results in excellent machining
accuracy even at high → path velocities. Feedforward control can be selected and
deselected on an axis-specific basis via the → part program.
Editor
The editor makes it possible to create, edit, extend, join, and import programs/texts/program
blocks.
Exact stop
When an exact stop statement is programmed, the position specified in a block is
approached exactly and, if necessary, very slowly. To reduce the approach time, exact stop
limits are defined for rapid traverse and → feed.
Exact stop limit
When all path axes reach their exact stop limits, the control responds as if it had reached its
precise destination point. A block advance of the → part program occurs.
External zero offset
Zero-point offset specified by the → PLC.
Fast retraction from contour
When an interrupt occurs, a motion can be initiated via the CNC machining program,
enabling the tool to be quickly retracted from the workpiece contour that is currently being
machined. The retraction angle and the distance retracted can also be parameterized. After
fast retraction, an interrupt routine can also be executed (SINUMERIK 840D).
Feed override
The programmed velocity is overriden by the current velocity setting made via the → machine
control panel or from the → PLC (0 to 200%). The feedrate can also be corrected by a
programmable percentage factor (1-200%) in the machining program.
Finished-part contour
Contour of the finished workpiece. See → Raw part.
1092
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Extended Functions