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The following parameter setting in mode CA fits a high pass filtering for bridging material gaps.
The Filter Upper-Limit is here deactivated with a value of 20, the Filter Lower-Limit is set to 2%. With a Lower-Limit
Keep-Time of 5 seconds the average value will be frozen for 5 seconds if a single measurement value is below the
limit of 2% of the average value. After 5 seconds the average value is deleted and a new average value building
starts. The Keep-Time function stops if a single measurement value lies within the Limit values.
5.15 Mode CC – automatic summation of a moisture quantity during one batch process
Simple PLCs are often unable to record moisture measurement values during one batch process with averaging
and data storage. Furthermore, there are applications without a PLC, where accumulated moisture values of one
batch process should be displayed to the operating staff for a longer time.
TRIME-GW Line works in mode CC with automatic summation. This increases the reliability for the moisture
measurement during one complete batch process. Due to precise moisture measurement also in the lower
moisture range, ,TRIME-GW Line can record, accumulate and store moisture values during a complete batch
process without an external switching or trigger signal.
The TRIME-GW Line “freezes” the analogue signal as long as a new batch process starts. So the PLC has time
enough to read in the “freezed” moisture value of the batch. For applications without a PLC the “freezed” signal
of the TRIME-GW Line can be used for displaying the moisture value to a simple 7-segment unit as long as a new
batch process starts.
With the parameter Moisture Threshold the TRIME-GW Line can be configured to the start moisture level where
the summation starts automatically. Due to an automatic recalibration of TRIME-GW Line, it is ensured that the
zero point will be precisely controlled. The start level could be variably set dependent to the plant. Recommended
is a level with e.g. 0.5% to 1%.
With the parameter No-Material-Delay a time range can be set, where the TRIME-GW Line is again ready to start a
new batch process. Are there short material gaps during a batch process which are shorter than the “No-Material-
Delay”, with no material at the probes surface, then the TRIME-GW Line pauses shortly with the summation. Is the
pause greater as the “No-Material-Delay” then the probe is ready to start a new batch process.
How can the mode CC be used, if the TRIME-GW Line cannot detect the „moisture threshold“ by itself, e.g. if
there is constantly material above the probe over a longer time:
In this case, a short interrupt of the probe´s
power supply, e.g for about 0.5 seconds with the help of a relay contact of the PLC, can restart the TRIME-GW Line
at the beginning of the material transport. After this short interrupt the TRIME-GW Line starts immediately with
the summarizing and averaging.
