Siemens SINUMERIK 840D sl Function Manual page 126

Safety functions integrated in the system/drive
7.3 Safe Stops A-F
An ESR is requested by the control monitoring channel. In parallel, the timer in MD36954
$MA_SAFE_STOP_SWITCH_TIME_E is started. The SBH function is automatically activated
after the timer expires.
● Effect:
The extended stop and retract that has been configured is also started.
● Alarm message:
The alarm message "STOP E initiated" is displayed.
● Acknowledgment:
For STOP E, an unintentional restart is prevented. The error can be acknowledged using
the NC-RESET key.
SGA "STOP E is active"
This signal indicates that STOP E is active.
0 signal: STOP E is not active
1 signal: STOP E is active.
The NC-controlled ESR is initiated by writing to the system variable $AC_ESR_TRIGGER=1
(also see /FB3/, M3 "Axis coupling and ESR"). To obtain the criteria for initiating, the following
SI system variables are used:
$VA_STOPSI:
Axis-specific system variable that contains the present stop. For a value of 4, a STOP E is
active for this axis.
$A_STOPESI:
Global system variable that with a value not equal to 0 indicates that a STOP E is active for
one particular axis. This variable saves the user having to search through all of the axes.
SGE deselect external STOP E
When a stop request is active, the SGA "STOP E is active" is set.
MD36977 $MA_SAFE_EXT_STOP_INPUT[3] defines the selection/deselection of the external
braking request, in this case "deselect external STOP E" (extended stopping and retraction
plus path braking).
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Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Safety Integrated