Festo CTEU-CO, Manual, Functions And Maintenance

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1. Commissioning
1-11
Festo P.BE-CTEU-CO-OP+MAINT-EN en 1101NH
1.5 Communication
When the fieldbus stations are switched on they all assume
the “pre-operational” status and wait for instruction from the
master controller.
1.5.1 Structure of communication
Pre-operational Only SDOs can be parameterised in this status. This paramet-
erisation corresponds to the asynchronous transmission
which is standard with most PLC controllers. Conversion to
e.g. synchronous transmission is possible if the communica-
tion parameters are written with the appropriate values from
the DS301 communication profile, but modifying the mapping
is not possible.
Operational After successful parameterisation the master controller can
switch the fieldbus stations to the “operational” status with a
special Network Management Telegram (NMT).
Communication via both SDOs and PDOs is possible in this
status. With the aid of the NMT telegrams you can switch
between the different states, if required.