IMKO TRIME-GW Series, Руководство пользователя

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For applications with non-continuous material flow, there is the option to optimise the control of the measurement
process via the adjustable filter values Filter-Lower-Limit, Filter-Upper-Limit and the time constant No-Material-
Keep-Time. The continual/floating averaging can be set with the parameter Average-Time.
Average Time in the measurement mode CA and CF
TRIME-GW Line establishes every 200 milliseconds a new single measurement value which is incorporated into
the continual averaging and issues the respective average value in this timing cycle at the analogue output. The
averaging time therefore accords to the “memory” of the TRIME-GW Line. The longer this time is selected, the
more inert is the reaction rate, if differently moist material passes the probe. A longer averaging time results in
a more stable measurement value. This should in particular be taken into consideration, if the TRIME-GW Line is
deployed in different applications in order to compensate measurement value variations due to differently moist
materials.
At the point of time of delivery, the Average Time is set to 4 seconds. This value has proven itself to be useful for
many types of applications. At applications which require a faster reaction rate, a smaller value can be set. Should
the display be too “unstable”, it is recommended to select a higher value.
5.14 Filtering at material gaps in mode CA and CF
A TRIME-GW Line is able to identify, if temporarily no or less material is at the probe head and can filter out such
inaccurate measurement values (Filter-Lower-Limit). Particular attention should be directed at those time periods
in which the measurement area of the probe is only partially filled with material for a longer time, i.e. the material
temporarily no longer completely fills the probe measuring field. During these periods (Lower-Limit-Keep-Time),
the probe would establish a value that is too low. The Lower-Limit-Keep-Time sets the maximum possible time
where the probe could determine inaccurate (too low) measurement values.
Furthermore, the passing of metal blades or wipers through the measuring field can lead to too high measurement
values (Filter-Upper-Limit). The Upper-Limit-Keep-Time sets the maximum possible time where the probe would
determine inaccurate (too high) measurement values.
Using a complex algorithm, TRIME-GW Line are able to filter such faulty individual measurement values. The
standard settings in the Measurement Mode CA and CF for the filter functions depicted in the following have
proven themselves to be useful for many applications and should only be altered for special applications.
It is appropriate to bridge material gaps in mode CA with Upper- and Lower-Limit Offsets and Keep-Time. For
example the Lower-Limit Offset could be adjusted with 2% with a Lower-Limit Keep-Time of 5 seconds.
If the TRIME-GW Line determines a moisture value which is 2% below the average moisture value with e.g. 8%,
than the average moisture value will be frozen at this value during the Lower-Limit Keep-Time of 5 seconds. In this
way the material gap can be bridged. This powerful function inside the TRIME-GW Line works here as a highpass
filter where the higher moisture values are used for building an average value, and the lower or zero values are
filtered out. In the following this function is described with SONO parameters.
Sufficient material for an accurately moisture
measurement value of e.g.8%
Material gaps over e.g. 3 seconds which must be bridged
for an accurately measurement with a Lower-Limit Keep-
Time of 5 seconds.