Siemens Simatic S7-1500R System Manual page 220

②
POWER ON → STOP
Transition Description
System state POWER ON → STOP
transition
The redundant system switches to the STOP system state after switch-on if:
Operating state
The mode selector is in the STOP position
•
transitions
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.
③
STOP → STARTUP
Transition Description
System state STOP → STARTUP
transition
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 selec-
•
tor is set to RUN
or
You set the mode switch from STOP to RUN.
•
The CPU that you switch from STOP to RUN first remains/becomes the pri-
mary CPU. It switches to the STARTUP operating state and processes
startup OB 100.
The backup CPU remains in STOP.
Operating state STOP → STARTUP
transition
After switch-on, the primary CPU switches to the STARTUP operating state
if:
The hardware configuration and program blocks are consistent
•
and
You set the 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.
•
S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA
Commissioning
9.4 Operating and system states
Effects
The primary CPU
clears the non-
retentive memory and
resets the contents of
non-retentive data
blocks to the initial
values of the load
memory. Retentive
memory and retentive
DB contents are re-
tained.
Effects
The primary CPU
clears the non-
retentive memory and
resets the contents of
non-retentive data
blocks to the initial
values of the load
memory. Retentive
memory and retentive
DB contents are re-
tained.
219