Siemens SIMATIC ET 200SP HA, System Manual, Page: 49 / 186

4.8.3 IO redundancy
IO redundancy
To configure the IO redundancy, plug 2 input/output modules (module pair) of the same type
next to each other on a special terminal block (TB45R...).
This terminal block connects the process signals of the two IO modules to a common process
terminal.
● There is less wiring work compared to connecting separate I/O modules, because the
interconnection of the process signals is integrated in the system.
● The redundant signal processing of the sensors and actuators on the module level
increases the availability of the system.
Application planning
Observe the following rules for installing I/O modules in IO redundancy:
Hardware rule
● The I/O modules must be approved for redundant operation. You can find this information
in the manual for the respective module.
● Redundantly deployed I/O modules must be identical, i.e. they must have the same article
number, the same hardware version and the same firmware version.
Mounting rule
I/O modules of the same type are plugged in pairs next to each other in the same IO device.
IO redundancy:
● Both slots are located in the same adapter module.
Read section "Selecting the carrier module (Page 30)".
● Both slots are in the same terminal block (TB45R).
Read the section "Selecting a terminal block for I/O modules (Page 32)".
Note
Specific wiring
Always read the documentation of the I/O module used.
Configuration
● Configure redundancy for the I/O module.
● The settings you make for an I/O module always apply to the module pair.
Plant planning
4.8 Redundancy and changes during operation
ET 200SP HA Distributed I/O system
System Manual, 08/2019, A5E39261167-AD
49