HBM WE2108 Series, Справочное руководство

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WE2108
HBM A1632-2.0 en
7 Further functions
7.1 Filtering
The WE 2108 has flexible analog and digital filter functions, in order to obtain
a stable measured value with a short transient time. The setting ex works is
sufficient as a rule for scales with up to 6000 divisions at 1
μ
V/e. Changes are
possible in the FiL menu:
•
”F_FiL” sets the cut−off frequency of the filter, see menu table.
•
”Icr” is an additional averaging over 1 ... 99 values. Use this function to
obtain a quiet measured value with very slow fluctuations of the measured
value (e.g. silo weighing under wind load). The measuring rate is not influ-
enced by this (moving average filter).
Also with the slowest filter setting it is guaranteed that the display does not
remain on the old value longer than one second after a load change (but see
7.1.2 ”Special filter for animal scales”).
7.1.1 Filter and standstill
Large values of ”Icr” increase the transient time. The standstill display (if acti-
vated) is adapted automatically. The dimensional unit or the C−character for
counting scale operation is displayed only if a stable value stands in the dis-
play as long as it corresponds to the transient time. With an abrupt change,
the dimensional unit therefore appears only after double the transient time.
7.1.2 Special filter for animal scales
This filter provides for a quiescent indication even in the case of animals mov-
ing on the scale platform. Shunt forces, e.g. by an animal supporting itself
on a fixedly mounted gate, must be avoided however.
Required settings
The filter is activated by means of the setting ”F_FiL” = 8 (or the interface
command ASF8). By varying the parameter ”Icr” the time behaviour of the fil-
ter can be adapted to the application:
Large values for ”Icr” provide for the filtration of major weight variations, but
also extend the duration up to the standstill display. The smallest meaningful
value for ”Icr” is 16. Smaller values are permitted but they lead to the same fil-
ter behaviour as the setting 16.
For the animal filter, a standstill criterion must always be active. The step
width can be freely selected(Parameter ”StiLL” = 1...9) from 1d to 9 d, the pre-
set time interval (1 / 0.5 / 0.2 seconds) does not have any influence. The set-
tings 0, 10 and 20 are treated as a setting 1 (test for 1d).