Fail Safe - Festo CPX-FB6 Manual

2. Commissioning

2.3.1 Fail safe

Festo P.BE-CPX-FB6-EN en 1207c
The CPX terminal supports special Fail Safe parametrisation.
System-specific I/O states can therefore be defined in the
event of an error.
Information on Fail Safe parametrisation can be found in the
CPX system description.
Note
In order to maintain defined I/O statuses in the event of an
error, the Sysfail evaluation of the Interbus master must be
activated.
The Sysfail evaluation in the Interbus master ensures that if
the PLC (CPU) stops or has an error, the exchange of process
data between the CPU and the Interbus interface module will
be synchronised.
This is to prevent 0-signals from being incorrectly transmitted
via the Interbus. Otherwise, useful Fail Safe treatment or pro-
gramming would not be possible.
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