Installation manual
Page 107 of204
6 Response times of the PSCBR
The response time is a very important safety related characteristic and must be strictly observed
for each application / application related safety function. The following chapter lists the response
times for individual functions, probably also in dependence on further parameters. If these data
are insufficient for a specific application you should validate the actual time behaviour against the
nominal behaviour by means of separate measurements. This applies also for the use of filter
functions in particular.
Safety note:
The response times must be determined for each application related safety function in
nominal behaviour and must then be compared with the actual value by using the
following data.
Special care must be taken when using filter functions. Depending on the filter length /
time the response time may be extended, which must be taken into account in the
safety related design.
In case of particularly critical problem formulations the temporal behaviour must be
validated by means of measurements.
During start-up of the device / alarm or fault reset the outputs may (depending on the
application program) become active over the response time period. This must be
taken into consideration when planning the safety function.
6.1 Response times in standard operation
The cycle time of the PSCBR system serves as basis for calculating the response times. In
operation this is
T_cycle = 8 ms
. The specified response times comply with the corresponding
maximum running time for the actual application within the PSCBR module. Depending on the
application, further, application dependent response times of the sensors and actuators used
must be added, in order to obtain the total running time.
Function
Response
time [ms]
Explanation
Activation of a monitoring function
by means of ENABLE with
subsequent shut-down via digital
output
24
*)
Activation of a monitoring function by means of
the ENABLE signal.
Activation of a monitoring function
by means of ENABLE with
subsequent shut-down via safety
relay
47
*)
Activation of a monitoring function by means of the
ENABLE signal.
Response of an already activated
monitoring function
including
PLC editing in case of position and
speed processing via digital output
16
*)
With a monitoring function that has already been
activated via ENABLE, the module requires one cycle
to calculate the current speed value. During the next
cycle after calculation of the monitoring function the
information is further processed and output by the
PLC, i.e. according to the implemented logic this will
lead to e.g. switching of an output.
Summary of Contents for PSCBR-C-10 Series
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