IFM KQ10 Series, Руководство по эксплуатации

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7
UK
5 Function
5.1 Measuring principle
The unit determines the level according to the capacitive measuring principle:
• An electrical field is generated and influenced by the medium to be detected�
This change to the field causes a measurement signal that is electronically
evaluated�
• The dielectric constant of a medium is important for its detection� For a
constant wall thickness, media with a high dielectric constant (e.g. water)
generate a strong measurement signal, media with a low dielectric constant
(e.g. oils) a correspondingly lower signal.
• The unit has 16 capacitive measuring segments (4). They generate
measurement signals depending on the degree of coverage�
3
200
228
11 11
28
1
2
14
3
4
Fig� 1: Measuring range and detection range of the sensor�
1:
Detection range (green)
2: Measuring range (red)
3: Limit range (grey)
4: Measuring segment (electrode)
Media can be detected within the detection range (1). The process value refers
to this range�
The measuring range (2) is always two sensor elements smaller than the
detection range� This is where accuracy is at its highest�
The limit range (3) is outside the detection range.
The sensor always provides the most recent valid process value� A process
value is valid if the device status has the value "0"�