Siemens SINUMERIK 840DE Programming Manual page 175

Example of deactivating travel to fixed end stop FXS=0
Deselection of the function triggers a preprocessor stop.
Traversing movements may and should be programmed in a block with FXS=0:
X200 Y400 G01 G94 F2000 FXS[X1] = 0
Meaning:
Axis X1 is retracted from the fixed stop to position X= 200 mm.
All other parameters are optional.
Caution
The traversing movement to the retraction position must move away from the fixed stop,
otherwise damage to the stop or to the machine may result.
The block change takes place when the retraction position has been reached. If no retraction
position is specified, the block change takes place immediately the torque limit has been
deactivated.
Example of clamping torque FXST, monitoring window FXSW
Any programmed torque limitation FXST is effective from the block start, i.e., the fixed stop is
also approached at a reduced torque. FXST and FXSW can be programmed or changed at
any time in the parts program:
FXST[X1] = 34.57
FXST[X1]=34.57 FXSW[X1]=5
FXSW[X1] = 5
The changes take effect before traversing movements in the same block.
Programming of a new fixed stop monitoring window causes a change not only in the
window width but also in the reference point for the center of the window if the axis has
moved prior to reprogramming. The actual position of the machine axis when the window is
changed is the new window center point.
Caution
The window must be selected such that only a breakaway from the fixed stop causes the
fixed stop monitoring to respond.
Description
The limit stop alarm can be suppressed from the parts program where necessary. This is
done by masking the alarm in a machine data and then activating this MD by means of
NEWCONF.
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
Programming Motion Commands
4.21 Travel to fixed stop (FXS, FXST, FXSW)
4-69