Microlectra Dinel DLS-27 Series, Instruction Manual

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DLS–27 © Dinel 14
1. Activate the sensor by inundation (immersion) the electrode into the medium. With this activation,
the sensor will change its status (LED lights ON or OFF).
2. Lower the sensitivity (by clockwise turning) until the sensors stop to react to this activation (dipping
into medium). The LED is in the same status as before the activation.
3. Turn from ½ to 1 rotation left from the threshold point (when the sensor just stops its reaction to
immersion). The sensor again changes the status and reacts again to the activation (flooding).
4. Check the setting.
If the medium is not available in advance, it is possible to use the basic setting from the producer and
after some time of operation (after sedimentation of dirt) to make any correction. However, it is always
necessary to know what the permittivity of the material is and to adapt the setting on the sensor. In the
“Sensitivity characteristics” table it is stated for each type, where the change of capacity corresponds
to the 1 rotation. A definite guide can be the fact that the flooding of the electrode in the length of
100 mm into the material with relative permeability Ɛ
r
= 2 will cause a change in the capacity about
1.5 to 2 pF (according to the type of electrode).
The hysteresis (position of the minimum and maximum level) can be changed by turning trimmer “H”
located under the right cover screw on the rear side. Clockwise turning makes the hysteresis higher,
reverse direction turning makes it lower. The lower the hysteresis is, the higher sensitivity is possible
to obtain, but the resistance against various disturbances get worse. For usual applications is optimal
hysteresis from ¼ to ¾ rotation of sensitivity trimmer.
After setting, it is necessary to properly tighten cover screws.
S
enSitivity characteriSticS
Type of sensor
Treshold
sensitivity
Hysteresis Sensitivity adjusting range
Temperature
stability
Rel. permittivity
of material
DLS–27_–10 0.1 pF 0.1 pF ... 2 pF Min. 8 pF (1 rot. = 1 pF) ± 0.004 pF/K Min. 1.4
DLS–27_–11 0.2 pF 0.2 pF ... 4 pF Min. 20 pF (1 rot. = 2 pF) ± 0.007 pF/K Min. 5.0
DLS–27_–20 0.1 pF 0.2 pF ... 3 pF Min. 15 pF (1 rot. = 1.5 pF) ± 0.006 pF/K Min. 1.3
DLS–27_–21 0.3 pF 0.3 pF ... 6 pF Min. 30 pF (1 rot. = 3 pF) ± 0.01 pF/K Min. 4.0
DLS–27_–22 0.3 pF 0.3 pF ... 6 pF Min. 30 pF (1 rot. = 3 pF) ± 0.01 pF/K Min. 4.0
DLS–27_–30 0.2 pF 0.2 pF ... 4 pF Min. 20 pF (1 rot. = 2 pF) ± 0.01 pF/K Min. 1.6
DLS–27_–31 0.3 pF 0.2 pF ... 5 pF Min. 25 pF (1 rot. = 2.5 pF) ± 0.01 pF/K Min. 5.0
DLS–27_–40 0.3 pF 0.2 pF ... 6 pF Min. 20 pF (1 rot. = 2 pF) ± 0.01 pF/K Min. 2.0
8. S
tatUS Signalization
In the following table are the types of inputs and the respective statuses (ON/ OFF) in the case of a
maximum and minimum level sensing. The signalling of the status of the sensor is indicated by the
red LED located on the upper area of the sensor beside the setting trimmers of the hysteresis (“H”)
and the sensitivity (“S”).
For minimum level sensing we recommend sensor with normally open output – NO, PO, RO. It is for
failure safety reasons – eventual failure of sensor behaves similarly as an exceeding of the limit state.
Analogically for maximum level sensing we recommend normally closed outputs – NC, PC, RC.