Siemens SINUMERIK 840D Operator's Manual page 328

A
Appendix
B Terms
Dynamic feedforward
control
E
Editor
Electronic handwheel
Exact stop
Exact stop limit
External work offset
F
Fast retraction from
contour
Feed override
Finished-part contour
Fixed machine point
A-328
Inaccuracies in the contour caused by following errors can be almost
entirely eliminated with the aid of dynamic, acceleration-dependent
feedforward control. The result is extraordinary machining precision
even at high tool path feed-rates. The feedforward control can be
individually selected and deselected for each axis in the parts
program.
The editor is used to create, modify, add to, compress, and insert
programs/texts/program blocks.
The electronic handwheels can be used to simultaneously traverse
selected axes manually. The meaning of the lines on the handwheels
is defined by increment weighting.
With a programmed exact stop instruction, the position stated in a
block is approached precisely and very slowly, if necessary. In order
to reduce the approach time, -> exact stop limits are defined for rapid
traverse and feed.
When all path axes reach their exact stop limits, the control responds
as if it had reached its destination point precisely. The -> part program
continues execution at the next block.
Zero offset specified by the -> PLC.
When an interrupt arrives a motion can be initiated via the CNC
machining program which allows the tool to be quickly retracted from
the workpiece contour currently being machined. The retraction angle
and the distance retracted can also be parameterized. An interrupt
routine can also be executed following the fast retraction of the tool.
(SINUMERIK FM-NC, 840D).
The programmed velocity is overridden by the current velocity setting
via the machine control panel or by the PLC (0-200 %). The feedrate
can also be corrected by a programmable percentage factor (1 -
200%) in the machining program.
Contour of the finished workpiece. See also -> blank.
A point defined uniquely by the machine tool, e.g. the reference point.
SINUMERIK 840D/810D Operator's Guide HMI Embedded (BEM) – 03.04 Edition
A
03.04
 Siemens AG, 2004. All rights reserved