Siemens SINUMERIK 828D Function Manual page 302

F1: Travel to fixed stop
6.2 General functionality
Functional sequence
The function is explained by the example below (sleeve is pressed onto workpiece).
Figure 6-1 Example of travel to fixed stop
Selection
The NC detects that the function "Travel to fixed stop" is selected via the command FXS[x]=1 and signals the
PLC using the IS DB31, ... DBX62.4 ("Activate travel to fixed stop") that the function has been selected.
If the machine data:
MD37060 $MA_FIXED_STOP_ACKN_MASK
(Monitoring of PLC acknowledgments for travel to fixed stop)
is set correspondingly, the system waits for the acknowledgement of the PLC using the IS DB31, ... DBX3.1
("Enable travel to fixed stop").
The programmed target position is then approached from the start position at the programmed velocity. The fixed
stop must be located between the start and target positions of the axis/spindle. A programmed torque limit is
effective from the start of the block, i.e. the fixed stop is also approached with reduced torque. Allowance for this
limitation is made in the NC through an automatic reduction in the acceleration rate.
If no torque has been programmed in the block or since the start of the program, then the value is valid in the
axis-specific machine data:
MD37010 $MA_FIXED_STOP_TORQUE_DEF
(Fixed stop clamping torque default setting)
is entered.
Basic Functions
302
Function Manual, 09/2011, 6FC5397-0BP40-2BA0