Siemens SINUMERIK 802D sl Function Manual page 22

Various Interface Signals (A2)
1.2 Signals from PLC to NCK
Spindle disable (for spindle):
If IS "Spindle disable" is set, no more speed setpoints are output to the speed controller in
openloop control mode and no more position partial setpoints are output to the position
controller in positioning mode. The movement of the spindle is thus disabled. The speed
actual value display displays the speed setpoint value. The spindle disable is cancelled via
"Reset" or program end (M2) and program restart. If interface signal "Spindle disable" is set
while a spindle is turning, the spindle is stopped according to its acceleration characteristic.
Deactivation:
Cancellation of the "Axis/spindle disable" (edge change 1 → 0) does not take effect until the
axis/spindle is stationary (i.e. an interpolation setpoint is no longer present). The new
movement begins with new specified setpoints. (E.g. new program block with movement
specifications in AUTOMATIC operating mode.)
Note: actual values vary between simulated and real axis!
Follow-up mode (V380x 0001.4)
If an axis/spindle is operating in followup mode, then its setpoint position is made to track the
current actual value position. The position setpoint in follow-up mode is not defined by the
interpolator but derived from the actual position value. Since recording of the actual position
value of the axis continues, it is not necessary to re-home the axis when follow-up mode is
cancelled.
Standstill, clamping and positioning monitoring are not effective in follow-up mode.
Effect:
The IS "Follow-up mode" is only of relevance if the drive controller enable has been removed
(e.g. by IS "Controller enable" = 0 signal or because of a fault in the control), or because
controller enable is being re-issued.
IS "Follow-up mode" = 1:
If "Controller enable" is removed the position setpoint of the relevant axis is continuously
corrected to the actual value. This state is signaled to the PLC by means of IS "Follow-up
mode active" (V390x 0001.3). If the "Controller enable" is enabled again and a part program
is active, a controlinternal re-positioning operation is initiated (REPOSA: linear approach with
all axes) to the last programmed position. Otherwise, the axis movement starts at the new
actual position (which may have changed).
IS "Follow-up mode" = 0:
If "Controller enable" is removed, the old position setpoint is maintained. If the axis is pushed
out of position, a following error between position setpoint and actual value results which is
corrected when IS "Controller enable" is set. The axis movement starts from the setpoint
position valid before the "controller enable" was removed. IS "Followup mode active" (V390x
0001.3) is set to 0 signal during the "Hold" state. Clamping or standstill monitoring is active.
22
Turning, Milling, Nibbling
Function Manual, 11/2012, 6FC5397-1CP10-5BA0