Supplementary information
16.14 Other options for connecting redundant I/Os
CPU 410-5H Process Automation/CPU 410 SMART
268 System Manual, 10/2013, A5E32631667-AA
You can react to redundancy errors of the S7-400H using the following organization blocks:
● OB 70, I/O redundancy errors
● OB 72, CPU redundancy errors
SFC 90 "H_CTRL" can be used to influence fault-tolerant systems as follows:
● You can disable interfacing in the master CPU.
● You can disable updating in the master CPU.
● You can remove, resume or immediately start a test component of the cyclic self-test.
● You can execute a programmed master-standby changeover. The following changeovers
are possible:
– The current standby CPU becomes the master CPU.
– The CPU in rack 0 becomes a master CPU.
– The CPU in rack 1 becomes a master CPU.
For detailed information on programming the blocks described above, refer to the STEP 7
Online Help.
Other options for connecting redundant I/Os
Redundant I/O at user level
If you cannot use the redundant I/O supported by the system (Chapter Connecting
redundant I/O to the PROFIBUS DP interface (Page 68)), for example, because the module
to be used redundantly is not in the list of supported components, you can also implement
the use of redundant I/O at the user level.
To Next Page
Loading...
