Siemens Simatic S7-1500R System Manual page 190

Automatic assignment
Requirement:
Both real CPUs of the redundant system have the same redundancy ID (e.g."1").
Options for automatic assignment:
● Both CPUs are in STOP. There is pairing between the two CPUs. The ERROR LEDs are
flashing red.
Procedure: Switch the left-hand CPU in the configuration to the RUN operating state.
Result: The right-hand CPU in the configuration changes its redundancy ID.
● The left-hand CPU in the configuration is in RUN operating state. The right-hand CPU in
the configuration is in STOP. There is no pairing between the two CPUs.
Procedure: Implement pairing between the two CPUs. Result: The right-hand CPU in the
configuration changes its redundancy ID.
● The left-hand CPU in the configuration is in RUN. The right-hand CPU in the configuration
is in POWER OFF. There is no pairing between the two CPUs.
Procedure: POWER ON the right-hand CPU in the configuration. Result: The right-hand
CPU in the configuration changes its redundancy ID.
S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA
Commissioning
9.3 Commissioning procedure
189