Functions Of The Addfem Soe; Front-End Function Soe - Siemens SIMATIC PCS 7 Operating Instructions Manual

Functions of the AddFEM SoE

The functions of the AddFEM SoE correspond to those of the AddFEM and are described in
the correspondingly named section in the "AddFEM (Front End Module)" operating
instructions. The document is available under the following link:
Internet (http://www.siemens.com/automation/service&support)
4.1

Front-end function SoE

Configuring the AddFEM SoE
The AddFEM SoE (6DL3100-8AC03) can be connected either redundantly or non-
redundantly via PROFIBUS DP to a host system, for example SPPA-T3000. The signal
states of the measuring sensors are acquired by the AddFEM SoE and transported to the
host cyclically via PROFIBUS DP with regular data telegrams for open-loop and closed-loop
control functions.
The event acquisition, time stamping and administration of events are executed by the
AddFEM SoE in parallel to and without limitation of the input and output functions. The entire
range of this supplementary function is called front-end function "SoE".
Event acquisition
A signal change is detected by AddFEM SoE with precision of one millisecond. For this
purpose, an extremely precise internal clock time is kept on each AddFEM SoE. The events
acquired and stamped with the precise time are stored temporarily by the front-end function
SoE in ring buffers and subsequently called by the host system via special acyclic telegrams.
The events from all event sources that are sorted in the right order on the basis of the time
stamp can be used to analyze an incident subsequently, for example. The transport of the
events provided once with exact time stamp is not time-critical.
Note
The exact synchronization of all the participating "clocks" of the overall system by the
GPS Time Server is of fundamental importance for subsequently sorting the events in the
right order.
AddFEM Sequence of Event
Operating Instructions, 03/2016, A5E00075541X-06
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