Siemens Simatic S7-1500R System Manual page 221

Commissioning
9.4 Operating and system states
④
STARTUP → RUN-Solo, STARTUP → RUN
Transition Description
System state STARTUP → RUN-Solo
transition
The redundant system switches from STARTUP to the RUN-Solo system
state if:
The primary CPU has initialized the PLC tags
•
and
the primary CPU has executed the startup blocks successfully
•
and
"Startup CPU only if compatible" is configured, there is feedback from all
•
IO devices before the end of the configuration time and all IO devices
match the configured hardware configuration or "Startup CPU even if
mismatch" is configured and the configuration time is up.
The backup CPU remains in STOP.
Operating state STARTUP → RUN
transition
The primary CPU switches to the RUN operating state if:
The CPU has initialized the PLC tags;
•
The CPU has executed the startup blocks successfully;
•
and
"Startup CPU only if compatible" is configured, there is feedback from all
•
IO devices before the end of the configuration time and all IO devices
match the configured hardware configuration or "Startup CPU even if
mismatch" is configured and the configuration time is up.
220
Effects
The process image is
updated and pro-
cessing of the cyclic
user program begins.
The outputs of the IO
devices are initialized.
S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA