Siemens SINUMERIK 840D sl Function Manual page 1657

Manual specification of a gear step
Outside a part program that is running, the gear step can also be changed without a request
from the NC or the machine. This is the case, for example, when a gear step is changed
directly by hand.
To select the appropriate parameter sets, the NC must be informed of the current gear step.
For this to work, the control or the part program must be in the reset state.
Constraints
Transfer of the gear step to the NC is initiated when
NC/PLC IS:
DB31, ... DBX16.0-16.2 (Actual gear step A to C) changes.
These three bits must be set continuously during operation.
Successful transfer is acknowledged with NC/PLC IS:
DB31, ... DBX82.0-82.2 (Set gear step A to C)
to the PLC.
NC/PLC IS:
DB31, ... DBX16.3 (Gear changed)
must not be set.
If position control is active when a new gear step is specified by the PLC
with NC/PLC IS:
DB31, ... DBX16.0-16.2) (Actual gear step A to C),
it is disabled throughout the gear change action.
NC stop during gear step change
The spindle cannot be stopped with NC/PLC IS:
DB21, ... DBX7.4 (NC stop)
if:
• The spindle is not yet in oscillation mode for the gear step change
• NC/PLC IS:
Basic logic functions: Spindles (S1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
DB31, ... DBX16.3 (Gear changed)
is not set.
Note
Options for aborting:
NC/PLC IS:
DB31, ... DBX2.2 (Delete distance-to-go/Spindle reset)
or
DB31, ... DBX16.3 (Gear changed)
with corresponding acknowledgment from actual gear step
(DB31, ... DBX16.0-16.2 (Actual gear step)).
Detailed Description
2.3 Configurable gear adaptation
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