High Availability Foundation Fieldbus - Siemens Simatic PCS 7 Function Manual

High availability solutions in PCS 7
4.3 Solutions for communication
4.3.5.7

High availability FOUNDATION Fieldbus

Functionality
PCS 7 enables the connection of field devices to the FOUNDATION Fieldbus H1 (referred to
only as FOUNDATION Fieldbus or FF from this point). A high availability FOUNDATION
Fieldbus is connected to the redundantly configured Compact FF Link. If the transmission path
fails, the communication path of the FOUNDATION Fieldbus is preserved as far as the spur
line to the field devices.
High availability communication solutions
The following communication solutions are offered to prevent a possible failure:
● Ring redundancy with the AFD (Active Field Distributor)
● Coupler redundancy with the AFS (Active Field Splitter)
Connection of the high availability FOUNDATION Fieldbus to PROFIBUS DP
You can connect a high availability FOUNDATION Fieldbus to the PROFIBUS DP. The
following variants can be realized:
● Connecting a high availability FOUNDATION Fieldbus via redundant bus link to a
redundant PROFIBUS DP
Installation with Compact FF Link (2x Compact FF Link)
● Connecting a FOUNDATION Fieldbus via redundant bus link to a redundant PROFIBUS DP
Installation with Compact FF Link (2x Compact FF Link)
We recommend the following configuration limits in PCS 7 when connecting FF devices using
AFD or AFS :
● You can connect an FF segment to a redundantly installed Compact FF Link.
● For the purpose of increasing availability when using ring redundancy (high availability
connection), connect a maximum of 4 field devices (one field device per spur line) to an
active field distributor AFD (maximum of 8 AFD to a redundant Compact FF Link).
● 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 the bus link must not be exceeded. This figure
includes all components connected to the FF segment.
90
High Availability Process Control Systems (V9.0)
Function Manual, 05/2017, A5E39221836-AA