IMKO Trime-GW, Operating Instructions Manual

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4 Special functions
The possible adjustments and special functions of TRIME
®
-GW described in this section are only
likely to be required very rarely. Altering these settings or effecting the special functions may cause
the device to behave incorrectly!
The settings mentioned hereafter in this context can be changed by using:

a special configuring connector (available as an special accessory).

TRIME®-WinGWData Software (free of charge). Downloadable from our website:
www.imko.de
4.1 Operating the TRIME
®
-GW measurement systems in an intermittent
flow of material
A classic example of intermittent material flow is the use of the probe in the discharge chute, where
material is only present for a brief period shortly after a discharge. For this and similar cases, two op-
tions exist for controlling the measuring process:
1. Control of the measuring process via the adjustable internal time constants Queue-
FillingTime and Queue-DischargeTime in conjunction with the similarly adjustable internal
time constant Error66-Delay.
2. Control of the measuring process via an external digital input signal HaltM which, for ex-
ample, can be produced by an PLC or a fill-level indicator.
4.1.1 Behaviour upon detection of air around the probe rods
The TRIME
®
-GW measurement system can detect when there is no more material around the probe
rods. When this situation arise, the measuring process is stopped immediately and the existing read-
ing “frozen”. After the adjustable time constant Error66-Delay has expired (cf. Table 1
the error 66: "Probe not fully immersed in grain" (cf. Table 1
is transmitted through the analogue output as "166.0". This is shown on the display unit as “E.EE” or
“166.0”, depending on the model.
Requiring special attention is the case where the periods in which the probe’s field of measurement
volume is only partially filled with the subject material, i.e. when the fill level “passes through” the pro-
be’s field of measurement during filling or discharge. During these periods, the device would record an
excessively low reading because a proportion of the field of measurement is occupied by air, which
contains only negligible amounts of water. The materials’ characteristics differ too in their “dielectricity”
upon which water-content measurement is based. Individual readings such as these must therefore be
discarded and prevented from inclusion in the calculation of the overall measurement value.
This overall measurement value or reading is still carried out in the manner described as “fluid mean
value” in Section
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Textmarke nicht definiert. . All that now has to be assured is that the determination of the mean value
is continued whilst using the set averaging time throughout the empty periods, and not started anew.
All that is not available during the empty period (plus the
Queue-DischargeTime and the Queue-
FillingTime ) are individual measurements that could contribute to the determination of the mean value.
The set “averaging time” is thus only composed of blocks of time in which valid individual
measurements can be taken.
4.1.2 Control via the internal time constants Queue-FillingTime and Queue-
DischargeTime
During discharge, not only the measurement must be frozen after air around the probe rods has been
detected, but the individual readings of the past
Queue-DischargeTime seconds, where the field of
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