Siemens SINUMERIK 840D sl Function Manual page 359

The following is assumed in the example below:
MD37050 $MA_FIXED_STOP_ALARM_MASK = 0
⇒ No alarm is generated in response to an error. A block change therefore takes place and
the error scenario can be evaluated via the system variable
Example
X300 Y500 F200 FXS[X1]=1 FXST[X1]=25 FXSW[X1]=5
IF $AA_FXS[X1]=2 GOTOF FXS_ERROR
G01 X400 Y200
Inoperative IS signals
The following IS signals (PLC ! NCK) are inoperative for axes at the fixed stop until the
function is deselected (incl. traversing motion):
• NST DB31, ... DBX1.3 ("Axis-/spindle disable")
• NST DB31, ... DBX2.1 ("Controller enable")
Actual position at fixed stop
System variable $AA_IM[x] can determine the actual position of the machine axis, e.g. for
test purposes after successful "travel to fixed stop."
Combination with other functions
"Measure with deletion of distance to go" (command MEAS) and "travel to fixed stop" cannot
be programmed at the same time in one block.
Exception:
One function is acting on a path axis while the other is acting on a positioning axis or both
functions are acting on positioning axes.
Contour monitoring
The axis contour monitoring function is inoperative while "Travel to fixed stop" is active.
Positioning axes
When "Travel to fixed stop" is applied toPOSA axes, block changes are made independently
of the fixed stop motion.
Basic logic functions: Travel to fixed stop (F1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Detailed Description
2.1 General functionality
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