Festo Checkbox Compact CHB-C-C, Руководство пользователя

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1. System summary
1-9
Festo P.BE-CB-COMP-EN en 0211a
1.5 Buffer zone
The buffer zone serves as a parts buffer for the following
machine e.g. assembly plant.
The Checkbox can monitor the highest and lowest filling
status of the attached buffer zones with one or two sensors
(only Checkbox PLC) and if there is a long blockage, it can
switch the small-parts conveyor on or off as required. When
connecting the buffer zone sensors, please observe the in-
structions in chapters 3.3 and 4.3.5.
Signal delay
The buffer zone inputs are processed by the Checkbox with a
debounce time. The sensor signal is only evaluated if it is
present for at least 1 second. This delay prevents each con-
veyed part from triggering the signal “Buffer zone full” when
it passes the sensor.
The delay time of 1 second between the registering of a con-
veyed part by the sensor and the interpretation of the signal
by the Checkbox must be taken into account when the buffer
zone sections are planned.
Planning the size of the buffer zone
The buffer zone sections (see Fig. 1/2) must be large enough
to enable the machine to operate, if possible, without inter-
ruption. Instructions on planning the size of the buffer zone
can be found in the following table.