Siemens SINUMERIK 808D ADVANCED Operating Instructions Manual page 380

Detailed descriptions of interface signals
4.8 Axis / spindle-specific signals
DB380x
DBX1.4
Edge evaluation: No
Signal state 1
Signal state 0
Special cases, errors, ... If the drive controller enable is withdrawn inside the control due to faults,
corresponding to ...
Note for the reader
DB380x
DBX1.5 / 1.6
Edge evaluation: No
380
Follow-up mode
Signal(s) to axis / spindle (PLC → NCK)
Signal(s) updated: Cyclic
Follow-up mode is selected for the axis / spindle by the PLC.
The means that the position setpoint continually tracks the actual value if
the controller enable for the drive is withdrawn.
As soon as the follow-up mode is effective, the interface signal:
DB390x DBX1.3 (follow-up mode active)
is set.
The actual value continues to be acquired and updated. If the axis / spindle
is moved from its current position by an external effect the zero speed and
clamping monitoring do not issue an alarm.
When the closed-loop control system is switched-on again, a control internal
repositioning operation is performed (REPOSA: linear approach with all
axes) to the last programmed position if a part program is active.
Follow-up mode is not selected (so-called holding).
When "controller enable" is removed the previous position setpoint is kept in
the control. If the axis / spindle is pushed out of position during this time a
following error occurs between the position setpoint and the position actual
value. This position difference is reduced to zero immediately by issuing
"controller enable" so that the previous setpoint position is restored.
Then, all the other axis movements start from the setpoint position valid
before "controller enable" was removed. When the position control is
switched in again the axis may make a speed setpoint jump.
Zero speed monitoring or clamping monitoring is still active.
In order to disable (switch-out) the zero speed monitoring, when clamping
an axis, the interface signal:
DB380x DBX2.3 (clamping operation running)
should be set.
then the following should be carefully observed:
Before an NC start, after the queued alarms have been successfully deleted
(i.e. inside the control, the controller enable is re-issued), then "holding"
should be activated. Otherwise, for an NC start and selected follow-up
mode, the traversing distance of the previous NC block would not be
executed due to the internal delete distance to go.
Notice:
When changing over from the "follow-up" state to the "hold" state and in the
control mode (a controller enable is issued), a delete distance-to-go
command is activated in the control. As a consequence, for example, an NC
block - in which only this axis is traversed - is ended directly.
DB380x DBX2.1 (controller enable)
Function Manual Basic Functions R1
Position measuring system 1 (PMS1) / Position measuring system 2
(PMS2)
Signal(s) to axis / spindle (PLC → NCK)
Signal(s) updated: Cyclic
Operating Instructions, 08/2013, 6FC5397-8EP40-0BA0
Parameter Manual