Siemens SIMATIC ET 200pro Operating Instructions Manual page 84

No. Operating mode transitions
③
STOP → STARTUP
④
STARTUP → STOP
⑤
STARTUP → RUN
⑥
RUN → STOP
CPU 1516pro-2 PN (6ES7516-2PN00-0AB0)
Operating Instructions, 11/2019, A5E35873416-AC
The CPU switches to "STARTUP" mode if:
The hardware configuration and program
•
blocks are consistent.
You set the CPU to "RUN" mode via the pro-
•
gramming device and the mode switch in is
RUN position.
or
You set the mode switch from STOP to RUN.
•
In the following cases the CPU returns from
"STARTUP" to "STOP" mode when:
The CPU detects an error during startup
•
You set the the CPU to "STOP" via the pro-
•
gramming device or mode switch.
The CPU executes a STOP command in the
•
Startup OB.
In the following cases, the CPU goes from
"STARTUP" to "RUN" mode when:
The CPU has initialized the PLC tags.
•
The CPU has executed the startup blocks
•
successfully.
In the following cases the CPU returns from
"RUN" back to "STOP" mode when:
The CPU recognizes an error that prevents
•
further execution.
The CPU executes a STOP command in the
•
user program.
You set the the CPU to "STOP" via the pro-
•
gramming device or mode switch.
Commissioning
8.4 Operating modes of the CPU
Effects
The CPU clears the non-retentive
memory, and resets the content of
non-retentive DBs to the start values of
the load memory. Retentive memory
and retentive DB contents are re-
tained.
The 500 most recent entries are re-
tained in the diagnostics buffer.
These operating mode transitions have
no effect on data.
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