Siemens SIMATIC S7-1500 System Manual page 276

Commissioning
11.4 Operating and system states
The display of the primary CPU indicates the copying progress.
Table 11-9 Copying the work memory
The backup CPU is busy accepting the data before it can also process the user program.
⑤
Making up backup CPU lag
In phase
The backup CPU sends a status message on its program progress to the primary CPU at each
cycle control point.
The display of the primary CPU indicates the lag of the backup CPU.
Table 11-10 Making up backup CPU lag
276
Primary CPU
RUN-Syncup
Syncup...
Copying work memory
to Backup PLC.
37%
Step 4 of 5
⑤
, the backup CPU catches up with the primary CPU.
Primary CPU
RUN-Syncup
Syncup...
Minimizing delay
between this PLC
and the Backup PLC.
00:00:07.359
Step 5 of 5
Backup CPU
CONNECTING...
Overview
CPU 1517H-3 PN
6ES7 517-3HP00-0AB0
Backup CPU
CONNECTING...
Overview
CPU 1517H-3 PN
6ES7 517-3HP00-0AB0
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD
?
?
OK
?
?
OK