ABB AC500-S Safety User Manual page 239

4.6.4.3 SF_WDOG_TIME_SET
Setting the maximum allowed cycle time of SM560-S Safety CPU
The SF_WDOG_TIME_SET function block allows the user to monitor the cycle time. The function block must
be called by the user during the first cycle. In order to update the outputs ACT_TIME and MAX_TIME, it is
necessary to call the function block in each cycle. If the function block is not available in the application, the
SM560-S and the application program will enter the SAFE STOP state after the first cycle. The watchdog
time is monitored prior to the output of the PROFIsafe telegrams.
If the cycle time is exceeded, an error message is an output and the Safety CPU enters the SAFE STOP
state. Reasonable values are longer than the basic SM560-S run time and at least two times shorter than the
F_WD_Time of the safety I/O module.
Only one function block instance must be used in the safety program, otherwise a warning is issued.
NOTICE!
The cycle time supervision takes place only in RUN (Safety) mode.
Table 17: FB Name: SF_WDOG_TIME_SET
Name Data Type
VAR_INPUT
EN BOOL
WDOG DWORD
RESET BOOL
VAR_OUTPUT
DONE BOOL
ACT_TIME DWORD
MAX_TIME DWORD
30.03.2017
Initial Value Description, Parameter Values
FALSE The function block is activated (EN = TRUE) or
deactivated (EN = FALSE) via input EN. If the
block is active, the current values are available at
the outputs.
16#00000000 Watchdog time in ms. The maximum allowed
value is 1000. If WDOG is > 1000, then SAFE
STOP state will be entered by SM560-S Safety
CPU.
FALSE TRUE sets MAX_TIME to 0.
FALSE Output DONE indicates that the set process is fin-
ished.
16#00000000 Actual SM560-S Safety CPU cycle time in ms
16#00000000 Maximal monitored SM560-S Safety CPU cycle
time in ms
AC500-S
Configuration and programming
AC500-S Libraries > SafetyExt_AC500_V22.lib
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