Siemens Simatic S7-1500R - Page 284

Procedure:
1.
POWER OFF/POWER ON the backup CPU. Result: The CPU becomes the backup CPU again
and changes to STOP.
2.
POWER OFF/POWER ON the primary CPU. Result: The CPU changes to RUN. The redundant
system switches to the RUN-Solo system state.
3.
Switch the backup CPU to POWER OFF/POWER ON again. Result: The redundant system
switches to the SYNCUP system state.
② No STARTUP after parameterization "Warm restart - operating mode before POWER
OFF"
Requirements:
•
You have parameterized "Warm restart - operating mode before POWER OFF" for both
CPUs.
•
The redundant system is in the RUN-Redundant system state.
Procedure:
1.
POWER OFF both CPUs at the same time.
2.
Set the mode selector for the primary CPU to STOP.
3.
POWER ON both CPUs again. Result: The redundant system switches to the STOP system
state.
② POWER ON → STOP
Transition Description Effects
System state trans
ition
Operating state
transitions
POWER ON → STOP
The redundant system switches to the STOP system state after switch-on if:
• The CPUs have different firmware versions
or
• The mode selector is in the STOP position
or
• The hardware configuration and program blocks are inconsistent
or
• The startup type "No restart (remain in STOP)" is set
or
• The startup type "Warm restart - Operating mode before POWER OFF" is set
and the redundant system was in STOP before POWER OFF.
The primary CPU clears
the non-retentive
memory and resets the
contents of non-retent
ive data blocks to the ini
tial values of the load
memory. Retentive
memory and retentive
DB contents are
retained.
③STOP → STARTUP
Transition Description Effects
System state trans
ition
STOP → STARTUP
The redundant system switches to the STARTUP system state if:
• You set a CPU to RUN via the PG/PC or the display and the mode selector is
set to RUN
or
• You set the mode switch from STOP to RUN.
The primary CPU clears
the non-retentive
memory and resets the
contents of non-retent
ive data blocks to the ini
tial values of the load
memory. Retentive
memory and retentive
284
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD
Commissioning
11.4 Operating and system states