Siemens Simatic S7-1500R System Manual page 217

Commissioning
9.4 Operating and system states
Cause of SYNCUP abort
The load on the redundancy connections between primary
and backup CPU is too high. As a result, the CPU is not
catching up with program execution on the primary CPU.
Maximum cycle time in the primary CPU exceeded
Primary CPU or backup CPU goes into STOP operating
state.
PROFINET ring interrupted
Supply voltage of the primary or backup CPU has failed.
216
Solution
Reduce the load on the redundancy connections between
primary and backup CPU by:
Reducing the post-processing of cyclic events (see
•
above)
Avoiding instructions that increase the synchronization
•
load, for example direct access, time access (for exam-
ple RD_SYS_T, WR_SYS_T, RD_LOC_T)
Reducing communication (HMI, PG/PG, Open User
•
Communication, etc.)
Complying with the configuration rules
•
Reduce the cycle time by setting a lower communication
•
load in the hardware configuration.
Configure a sufficiently long maximum cycle time.
•
If there is an OB 80 (timeout OB) in the downloaded user
•
program, it is called by the operating system to tolerate
the cycle time being exceeded (see section Start events
(Page 153)).
Switch the primary CPU or backup CPU into RUN operating
state.
Replace defective PROFINET cables or PROFINET devices
in the PROFINET ring.
Restore the supply voltage. Replace a defective PM/PS.
System Manual, 10/2018, A5E41814787-AA
S7-1500R/H redundant system