Festo Контроллер позиционирования CPX-CMPX - Manual (Page 201)

C. General information on parametrisation
C−3
Festo P.BE−CPX−SYS−EN en 0902e
C.1 Input debounce time
Fundamentals
Input debounce times are specified in order to eliminate inĆ
terfering changes of signal edge during switching procedures
(bouncing of the input signal). For example, mechanical
switches generate brief undesired signal edges during switchĆ
ing procedures. The signal states which are thereby produced
can cause interference in the control sequence and should
therefore frequently be suppressed.
Interfering, undesired signal edges can be suppressed by
a PLC program in the higher−order controller. Interference can
therefore be avoided. With the CPX terminals, undesired sigĆ
nal edges can be suppressed simply by parametrisation.
CPX parametrisation
With the CPX terminals, the input debounce time can be set
with an appropriate module parameter. The possible input
debounce times therefore depend on the particular type of
module. Typical input debounce times are: 0.1 ms, 3 ms (typiĆ
cal presetting), 10 ms and 20 ms.
Mode of operation
Changes of edge in the sensor signal will be accepted as a
logical input signal (see Fig. C/1) only when the specified
debounce time has expired.