Signals To Channel (Db21; Signals From Channel (Db21 - Siemens SINUMERIK 840Di Function Manual

2.1.6

Signals to channel (DB21, ...)

DB21, ...
DBX6.2 Delete distance-to-go (channel-specific)
Edge evaluation: no
Signal state 1 or Delete distance-to-go (channel-specific):
edge change 0 → 1
IS "Delete distance-to-go (channel-specific)" for path axes is only active in AUTOMATIC mode.
The rising edge of the interface signal is only effective for the axes involved in the geometry
grouping. These are also stopped with a ramp stop and their distance-to-go deleted (setpoint -
actual value difference). Any remaining following error is not removed. The next program block is
then started.
IS "Delete distance-to-go (channel-specific)" is therefore ignored by positioning axes.
Note:
IS "Delete distance-to-go" does not influence the running dwell time in a program block with dwell
time.
Signal state 0 or No effect
edge change 1 → 0
Signal irrelevant Positioning axes
for ...
Application To terminate motion because of an external signal (e.g. measuring probe)
example(s)
Special cases, Delete distance-to-go (channel-specific)
errors, ....
When the axes have been stopped with IS "Delete distance-to-go" the next program block is
prepared with the new positions. After a "Delete distance-to-go", geometry axes thus follow a
different contour to the one originally defined in the part program.
If G90 is programmed in the block after "Delete distance-to-go" it is at least possible to approach
the programmed absolute position. On the other hand, with G91, the position originally defined in
the part program is no longer reached in the following block.
Corresponding to .... DB21, ... DBX6.2 (delete distance-to-go (axis-specific))
2.1.7

Signals from channel (DB21, ...)

DB21, ...
DBX36.6 Channel-specific NCK alarm is active
Edge evaluation: no
Signal state 1 or At least one NCK alarm is present for this channel.
edge change 0 → 1
This means that the group interface signal is also set
DB10 DBX103.0
(NCK alarm is present).
The PLC user program can interrogate whether processing for the channel in question has been
interrupted because of an NCK channel:
DB21, ... DBX36.7 (NCK alarm with processing stop present).
NC/PLC Interface Signals (Z1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Signal(s) updated: cyclic
Signal(s) updated: cyclic
2.1 Various interface signals and functions (A2)
Detailed Description
2-25