Instruction Manual

C. General information on parametrisation
C−5
Festo P.BE−CPX−SYS−EN en 0902e
C.2 Signal extension
Fundamentals
Signal extension times are specified when very shor t signals
are to be taken into account in the control process. Short
signals can occur, e.g. when an intermediate position is ex
ceeded and evaluation is necessary in order to produce a
time−optimised consequent process before an end position is
reached.
Depending on the type of
sensor, the length of the signal,
which is generated when the intermediate position is ex
ceeded, can fluctuate according to the positioning speed.
There is a danger here that the short signals are not always
recognised" due to long cycle times of the higher−order
controller.
With CPX terminals, a signal extension time can
be defined by
parametrisation of the appropriate input signal. Short signals
will then also be recognised reliably by the higher−order con
troller.
CPX parametrisation
With the CPX terminals, the signal extension time for the mo
dule is set with the appropriate module parameter. The poss
ible signal extension times depend on the type of module.
Typical signal extension times are: 0.5ms, 15 ms, 50 ms and
100 ms.
The signal extension time for each channel can be
activated
or deactivated with a further channel−orientated module para
meter. When preset, the signal extension time is inactive.