Cpu Memory Reset - Siemens SIMATIC S7-1500 System Manual

Commissioning

10.6 CPU memory reset

No. Operating mode transitions
⑤
STARTUP → RUN
⑥
RUN → STOP
10.6 CPU memory reset
Basics of a memory reset
A memory reset on the CPU is possible only in the STOP mode.
During memory reset, the CPU is changed to a so-called "initial status".
This means that:
● An existing online connection between your programming device/PC and the CPU is
terminated.
● The content of the work memory and the retentive and non-retentive data (applies only to
manual memory reset by the user) are deleted.
● The diagnostics buffer, time of day, and IP address are retained.
● Subsequently the CPU is initialized with the loaded project data (hardware configuration,
code and data blocks, force jobs). The CPU copies this data from the load memory to the
work memory.
Result:
– If you set an IP address in the hardware configuration ("Set IP address in the project"
– Data blocks no longer have current values but rather their configured start values.
– Force jobs remain active.
158
The CPU goes to the "RUN" mode in the following
cases of "START-UP":
The CPU has initialized the PLC tags.
•
The CPU has executed the startup blocks
•
successfully.
The CPU returns to the "STOP" mode in the following
cases of "RUN":
An error is detected that prevents continued
•
processing.
A STOP command is executed in the user program.
•
The programming device or the mode selector sets
•
the CPU to "STOP".
option) and a SIMATIC memory card with the project is in the CPU, this IP address is
valid after the memory reset.
Effects
Automation system
System Manual, 12/2014, A5E03461182-AC