Functions
10
10.1
Redundancy with Compact FF Link
Usage
You can operate the bus link on a SIMATIC S7-400H redundantly (e.g. on CPU 410‑5H).
Requirements
● Installation on BM Compact FF Link (active bus module for Compact FF Link)
The bus module enables a fast switchover, when needed, thanks to the active
communication between the two Compact FF Links.
● 2 x Compact FF Links on BM Compact FF Link
The installation rules for the bus module and the Compact FF Links can be found in section
● In redundancy mode, the same PROFIBUS address must be set for both Compact FF Links.
● Connect the left Compact FF Link to the S7-400H via the DP master system that is
connected to the left CPU or Rack 0.
Connect the right Compact FF Link to the S7-400H via the DP master system that is
connected to the right CPU or Rack 1.
Note
The SYNC/FREEZE function must not be activated during redundancy mode.
S7-400H as DP Master
DP master 1 and DP master 2:
● The DP master execute the same user program.
● The DP masters have the same parameter assignment and configuration for the Compact
FF Link.
Power supply
You can find information on the power supply of a bus link in redundancy mode with
2 x Compact FF Links in section "Connecting the power supply (Page 37)".
Additional information
You can find information about article numbers in section Preface (Page 7).
Compact FF Link
Operating Instructions, 03/2015, A5E35651552-AA
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