Siemens SINUMERIK 840D sl Function Manual page 618

Detailed description
2.6 Block search Type 5 SERUPRO
Repositioning with controlled REPOS
At any point during processing, a part program can be interrupted and an ASUB started with
a REPOS.
For path axes, the REPOS mode can be controlled by the PLC via VDI signals to reposition
on the contour. This mode is programmed in the part program and defines the approach
behavior. See "Repositioning to contour with controlled REPOS".
The REPOS response of individual axes can also be controlled via VDI signals
and is enabled with:
MD11470 $MN_REPOS_MODE_MASK BIT 2==1
.
Path axes cannot be influenced individually. For all other axes that are not geometry axes,
repositioning of individual axes can be prevent temporarily and also delayed. VDI signals can
be used to subsequently reenable or to continue blocking individual channel axes that
REPOS would like to traverse.
Danger
Via the signal:
DB31, ... DBX2.2 (delete distance-to-go, axis-specific)
the following dangerous behavior results during the "Prevent repositioning of individual axes"
via:
MD11470 $MN_REPOS_MODE_MASK (Bit 2==1).
As long as an axis is programmed incrementally after the interruption, the NC approaches
different positions than those approached with no interruption (see example below).
60
Basic logic functions: Mode group, channel, program operation, reset response (K1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0