Festo FB16 Electronic Manual page 120

VIFB16 - 03/05
Event
FIPIO bus interruption
Internal fault in the valve terminal
• Module fault
• Output short circuit/overload
Device to STOP
Fig. 4/16: Output shutdown behaviour
4-38
4. Commissioning
Shutdown behaviour of outputs
(HOLD/STOP)
In normal operation the valve terminal outputs
behave in accordance with the commands from
the PLC program. At the end of each operating
cycle they will be set/reset in accordance with
the values sent by the application program.
However, a number of events can occur during
operation which require to be differentiated:
•
STOP - the outputs of the valve terminal are
switched off on every event (error).
•
HOLD - in certain cases the outputs retain
their current status.
The following table shows the events on which a
HOLD operation is possible:
Shutdown behaviour
optional shutdown of output (STOP)
or
maintenance of the last value received
(HOLD)
0506b