Safety
Fail-Safe Systems
A5E00085588-03
7-19
You can obtain the overall signature of the program and the signatures of the
blocks in the CPU by choosing the Options > Edit Safety Program menu
command. When a comparison with the online program is made, it is indicated
whether the source, load memory and working memory match up (this enables
impermissible data manipulation to non-interconnected fail-safe input parameters
in the working memory to be detected).
You can check whether a Safety Program in the CPU is really the one you
expected by carrying out the following steps:
1.
Choose the Options > Edit Safety Program menu command in SIMATIC
Manager and activate "Online" in the dialog box. The signature displayed in the
dialog box must match the signatures in the accepted printout (in the text and
in the footer).
2.
To detect impermissible manipulation (e.g. via test mode in CFC) in the
working memory of the CPU, choose "Compare..." and compare the accepted
program with the online program in the dialog box. Any manipulated
parameters are displayed there. This step is imperative for acceptance.
3.
In the case of fault-tolerant S7 FH systems, the above steps must be carried
out for both CPUs in the online view of SIMATIC Manager.
When you repeat downloading or repeat checks of the Safety Program, carry
out this overall signature check again.
Please note that the overall signature is also available from “F_PRG_SI input the
F_SHUTDN function block within the @F_ShutDn CFC.
Summary of Contents for SIMATIC S7 F
Page 8: ...Important Information Fail Safe Systems viii A5E00085588 03 ...
Page 16: ...Contents Fail Safe Systems xvi A5E00085588 03 ...
Page 38: ...Product Overview Fail Safe Systems 1 22 A5E00085588 03 ...
Page 56: ...Getting Started Fail Safe Systems 2 18 A5E00085588 03 ...
Page 70: ...Safety Mechanisms Fail Safe Systems 3 14 A5E00085588 03 ...
Page 115: ...Programming Fail Safe Systems A5E00085588 03 5 33 Examples Receive Block Send Block ...
Page 154: ...Programming Fail Safe Systems 5 72 A5E00085588 03 ...
Page 166: ...Operation and Maintenance Fail Safe Systems 6 6 A5E00085588 03 ...
Page 332: ...Fail Safe Blocks Fail Safe Systems 8 144 A5E00085588 03 ...
Page 344: ...References Fail Safe Systems B 2 A5E00085558 03 ...
Page 350: ...Glossary Fail Safe Systems Glossary 6 A5E00085588 03 ...