Siemens SIMATIC S7 F, Manual

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Fail-Safe Blocks
Fail-Safe Systems
8-52
A5E00085588-03
8.5.4 F_R_R
Function
This block safely receives 5 data items of the data type F_REAL sent from another
F-run-time group from the F_S_R block.
The received data comes to the outputs RD_R_xx for further processing by other
blocks.
The input S_DB must be connected with the output of the same name of the
sending block.
The input TIMEOUT must be assigned a value for monitoring the safety-related
communication. If an updated frame is not received during this time, the system
function SFC F_CTRL is called. See "Monitoring Safety-Related Communication
Between F Run-Time Groups".
Startup Characteristics
In the first cycle after a cold or warm restart, the block outputs the substitute values
configured at the SUBR_xx inputs. The output of the substitute values depends on
the configured execution times of the cyclic interrupts and occurs as long as the
value F_TRUE is at the output SUBS_ON, but only until the monitoring time
TIMEOUT elapses.
I/Os
Name Data Type Explanation Default
Inputs: TIMEOUT F_TIME Monitoring time in ms for vital-
sign monitoring T#0 ms
S_DB F_WORD Instance DB no. of the
associated F_S_R 0
SUBR_00 F_REAL Substitute value for receipt
data 00 0
... ...
SUBR_04 F_REAL Substitute value for receipt
data 04 0
Outputs: SUBS_ON F_BOOL Substitution values are output 0
RD_R_00 F_REAL Receipt data 00 0
... ...
RD_R_04 F_REAL Receipt data 04 0