
PROGRAMMING
B–63534EN/02
22. RISC PROCESSOR
621
CAUTION
1 The function for determining the feedrate with the cutting
feed is effective only when the tool is parallel with the
Z–axis. Thus, it may not be possible to apply this function,
depending on the structure of the machine used.
2 In the function for determining the feedrate with the cutting
feed, the travel direction on the Z–axis is determined with
the appropriate NC command. If, therefore, manual
intervention is performed on the Z–axis with manual
absolute on, or if a mirror image is applied on the Z–axis, the
direction on the Z–axis cannot be determined. When using
the function for determining the feedrate with the cutting
load, do not use these functions.
3 When performing three–dimensional coordinate conversion,
determine the descent angle on the Z–axis using the
converted coordinate system.
In a block in which automatic feedrate control is enabled, all feed
commands (F commands) can be ignored by setting parameter NOF (bit
7 of No. 8451). The term feed commands, as used here, refer to the
following commands:
(1) Modal F commands before the block in which automatic feedrate
control is enabled
(2) F commands and modal F commands in the block in which automatic
feedrate control is enabled
When the F commands are ignored, it is assumed that the upper feedrate
limit specified for parameter No. 8465 is specified.
Note, however, that any issued F commands and modal F commands are
stored within the CNC.
Thus, in a block in which automatic feedrate control changes from the
enabled state to the disabled state, the modal values of the F commands
described in 1 and 2 described above are used as modal F commands,
instead of the modal values of the F commands calculated by automatic
feedrate control.
The following gives the specifications of override to a feedrate
determined by functions such as deceleration based on feedrate difference
in look–ahead acceleration/deceleration before interpolation and
deceleration based on acceleration rate in AI High Precision Countour
Control.
– When bit 3 (OVR) of parameter No. 8459 = 0
The conventional specifications apply.
Override is invalid for deceleration functions such as deceleration
based on feedrate difference and deceleration based on acceleration
rate.
– When bit 3 (OVR) of parameter No. 8459 = 1
Override is valid for deceleration functions such as deceleration based
on feedrate difference and deceleration based on acceleration rate.
Ignoring F code
commands
Override to a determined
feedrate