Rules for Failsafe Operation of an S5-95F
S5-95F
The COM 95F Software Package Supports the Acceptance and Approval Procedure
The COM 95F software package helps you initialize the system parameters (DB1), and also provides
a print function for hardcopy documentation. For more detailed information on the COM 95F
software, please see the COM 95F Manual.
Note
It is a requirement of systems which require an acceptance test that the DB1 parameters
be initialized with COM 95F. The COM 95F software has a user-friendly menu system,
and checks all entries for validity and syntax errors. COM 95F is obligatory to the system
approval procedure. The operator/installation engineer must make sure that the COM
95F software package is available to the inspector at the time of the system acceptance
test.
18.1.1 Planning Phase
Even while planning your system, you should contact the approving authority and clarify the following
points:
Safety Requirements
Find out which standard (e.g. DIN VDE 0116) contains the safety requirements for your system and
the class to DIN V 19250.
Risk Analysis
In the risk analysis, the inspector decides which of your system's subprocesses are relevant to
failsafety. If some subprocesses are relevant to failsafety while others are not, a risk analysis also
becomes necessary for the latter.
Objectives
The inspector decides upon the objectives of your system as regards failsafety, and upon the criteria
for a transition of the system to a safe state.
The following questions must be answered:
•
In what situations must the entire system be shut down?
•
In which cases would it be sufficient to shut down only subprocesses?
•
Is the passivation and depassivation of I/Os permitted?
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EWA 4NEB 812 6210-02
