SICK UM18-2 Pro, Руководство по эксплуатации

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8014865/ZUJ3/2018-11-29 • © SICK AG • Subject to change without notice 29
Commissioning
7.5 Measured value filter
Filter settings The following filter settings can be selected for the UM18-2 Pro ultrasonic
sensors using " Adapter":
Filter F00 provides an unfiltered output for the measured values.
This mode is not permitted, as undesired EMC faults could result.
Decreasing distance values are checked by filters F01 and F02 only for
plausibility and then output without any further conditions. After checking
for plausibility, increasing distance values are tracked only if they do not
exceed a specified tolerance range for the rate of increase. If the deviations
are too great, they are classified as interference variables by the software
and bridged for an adjustable holding time according to filter strength P.
Filter F01 provides interference protection against individual pulses such
as EMC spikes in connection with protection against measured value jumps
that are away from the sensor. The filter is suitable for bridging signal
jumps.
Filter F02 provides interference protection against individual pulses
such as EMC spikes in connection with protection against very brief
measured value jumps away from the sensor. The filter reacts very quickly
to measured values near the sensor and provides a smoothed output of
measured values based on approximately arithmetic averaging. This filter
is therefore especially suitable for smoothing fluctuating measured values.
Smoothing according to the filter strength P.
Filter F03 and F04 do not include a plausibility check. Thereby they waive
an interference protection against single interfering impulses and thus
resulting measurement value jumps with direction to smaller (F03) or larger
(F04) distance values. In return they react very quickly to measurement
value changes in the preferred distance level (F03: near sensor; F04: away
from sensor) and provide a smoothed output of measurement values in
this distance level, according to filter strength P.
In the opposite direction an adjustable holding time as well as an averaging
take effect, both operating according to filter strength P.
With filter F03 background reflections of unexpected objects are faded out.
With filter F04 foreground reflections of unexpected objects (e.g. stirring
tools) are faded out.
Filter overview
Filter feature Plausibility check Dwell time Preferred distance
level
Averaging
Functionality Interference
protection against
individual pulses
(EMC)
Bridging measured
value jumps
Near sensor/away
from sensor
"Smoothing"
the output of
measured values
Filter F00 (No filter) No No No preference No
F01 (Approximation filter) Yes Yes Near sensor No
F02 (Average value filter) Yes Low Near sensor Yes
F03 (Foreground filter) No Yes Near sensor Yes
F04 (Background filter) No Yes Away from sensor Yes
Table 6: Filter overview