Siemens sinumerik 840D sl Function Manual page 375

2.7.15 Boundary conditions
Operational performance of the components
The "drives, motors, transmitters" axis/spindle components participating in "Extended stop
and retract" must be operational. If one of these components fails, the full scope of the
described reaction no longer applies. Axis-specific servo or drive alarms describing the
failure of one of these components are also implicitly signaling that the configured stop or
retract reaction of the axis (axes)/spindle(s) is no longer (fully) available.
Motion synchronous actions
Motion synchronous actions are executed in the interpolator cycle. If there are many motion-
synchronized actions, the runtime of the control for processing the cyclical interpretation of
conditions in the synchronized actions is increased. The selected sources and the reactions
to be assigned can "only" be evaluated or triggered in the interpolator cycle.
Priority
Each drive independent reaction has a higher priority than the corresponding NC-controlled
reaction (reason: when broadcast mode is activated for the drive, each drive-independent
reaction becomes directly active).
POWER ON
If drive-independent stop or retract has been triggered, the drive software requires a
subsequent POWER OFF/POWER ON (drive behavior as with serious errors, see also
Communications Failure).
Special functions: Axis Couplings and ESR (M3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Detailed description
2.7 Extended stop and retract (ESR)
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