Siemens SINUMERIK 840D sl Function Manual page 303

If a pending stop condition is selected as an abort criterion via machine data
MD32084 $MA_HANDWH_STOP_COND
or
MD20624 $MC_HANDWH_CHAN_STOP_COND
during handwheel travel, once again no motion command is output (compatibility), but the
corresponding travel request is output.
When the stop condition is overridden, the corresponding "travel request" PLC signal is
reset, as an abort is present. The stop condition is no longer active, but the axis cannot be
traversed as the stop condition has caused an abort.
In addition, either the path default
(MD11346 $MN_HANDWH_TRUE_DISTANCE == 1 or == 3)
is active, or the handwheel is moved continuously, i.e. provides pulses.
Figure 4-4
If a stop condition is activated during the handwheel-travel movement, the movement is
aborted and the "travel request" and "motion command" are reset.
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Signal/timing diagram, handwheel travel when stop condition is abort criterion
Manual and Handwheel Travel (H1)
Handwheel travel in JOG
303