Siemens SIMATIC PCS 7 Function Manual page 75

● You can connect one FF segment to the FF Link .
● For the purpose of increasing availability when using ring redundancy (fault-tolerant
● Connect an active field splitter (AFS) to a redundant coupler in the case of coupler
● 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
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 (V8.0)
Function Manual, 03/2012, A5E02779471-02
connection), connect a maximum of 4 field devices (one field device per spur line) to an
active field distributor AFD(maximum of FDC 157 8 AFD to a redundant 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.
components connected to the FF segment.
Connection to a redundant PROFIBUS DP
Fault-tolerant Solutions in PCS 7
3.3 Solutions for communication
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