Downloading Changes/Complete Downloading; Tracking Changes In The Safety Program - Siemens SIMATIC PCS 7 Operating Manual

Changes, tracking changes, and acceptance

9.5 Downloading changes/Complete downloading

9.5 Downloading changes/Complete downloading
Standard program
In an S7-400 F/FH system with a safety and standard program, changes can be made in the
standard program in exactly the same way as with a standard system.
However, since the fail-safe program may also be affected by a program error in the
standard program (e.g. an infinite loop in a user block), changes in the standard program
should be treated in the same way as changes in the safety program.
Safety program
The procedure for downloading changes/complete downloading of programs with F-blocks is
identical to the one used for the standard program. Additionally, safety mode must be
deactivated before downloading changes and then reactivated once this is complete. Prior to
loading the safety program, perform a consistency test. The signatures in the program
information section and in the footer of the safety printout must be the same.
Note
You can find more information in section Safety mode and downloading the safety program
(Page 121).
During a complete download, the CPU is stopped and must be restarted once the download
is complete. When the CPU starts up, it goes into safety mode.
9.6

Tracking changes in the safety program

Backing up projects
In order to track changes, it is necessary to back up the project at regular intervals both
before and after changes are made. A plant-wide decision should be taken regarding where
project backups are to be stored and how the individual versions are to be named.
178
Compendium Part B - Process Safety (V8.2)
Operating Manual, 07/2016, A5E35031794-AB