Festo SFC-LAC CO Series, Руководство пользователя

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B. Parametrizing in accordance with FHPP−FPC
B−73
Festo P.BE−SFC−LAC−CO−EN en 0708NH
B.3 Status machine FHPP
Notes on representing the status machine.
The transition T3 changes to status S4, which itself contains
its own sub−status machine, the states of which are marked
with SAx" and the transitions of which are marked with
TAx".
The transition Tx applies globally for all sub−states SAx,
i.e. T4, T5** and T6* are derived from each SAx sub−status.
Each Tx transition automatically has higher priority than a TAx
transition.
Such a structure is a simplification. It is not therefore
necessary to define out of each SAx status a sparate
transition as per S3 for the reaction to Stop.
Reaction to faults
T7 (Fault recognized") has the highest priority (and receives
the asterisk * ").
T7 is then derived from S5+S6 when a fault with higher prior
ity occurs. This means that a serious fault can suppress a
simple fault.