Special Instructions For S7-1500R/H Redundant Systems; Disabling/Enabling Syncup With The Rh_Ctrl Instruction - Siemens SIMATIC S7-1500 System Manual

*Exception: In the RUN-Redundant system state, a higher-priority OB 83 "Pull/plug modules"
does not interrupt the execution of an OB 82 "Diagnostic interrupt".
Note
Communication
Communication (for example test functions with the PG/PC) always operates with a priority of
15. To avoid unnecessarily prolonging the program runtime in the case of time-critical
applications, make sure that these OBs are not delayed or interrupted by communication.
Assign a priority > 15 for these OBs.
Reference
Additional information on organization blocks is available in the STEP 7 online help.
10.4

Special instructions for S7-1500R/H redundant systems

10.4.1

Disabling/enabling SYNCUP with the RH_CTRL instruction

Introduction
You use the "RH_CTRL" instruction to disable SYNCUP or to enable the execution of the
SYNCUP for the S7-1500R/H redundant system. The disable applies:
• Until you cancel it with the "RH_CTRL" instruction or
• Until the S7-1500R/H redundant system switches to the STOP system state
Figure 10-2
S7-1500R/H redundant system
System Manual, 01/2024, A5E41814787-AF
10.4 Special instructions for S7-1500R/H redundant systems
RH_CTRL instruction
Basics of program execution
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