Siemens SIMATIC PCS 7 Function Manual page 81

● Connect an active field splitter (AFS) to a redundant coupler in the case of coupler
redundancy. Connect the field devices via AFD (max. 8 AFD). For the purpose of increasing
availability, connect a maximum of 4 field devices per AFD.
● You can connect a maximum of 31 field devices per FF segment.
● The maximum power consumption of 1 A must not be exceeded. This figure includes all
components connected to the FF segment.
Configuration
Examples for connections of field devices via AFD and AFS are shown in the following figures.
Figure 3-3
Fault-tolerant Process Control Systems (V8.1)
Function Manual, 11/2014, A5E34878832-AA
Connection to a redundant PROFIBUS DP
Fault-tolerant Solutions in PCS 7
3.3 Solutions for communication
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