Endress+Hauser nivocompact FTC 831, Инструкция по установке и эксплуатации

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Determining the Switching Point
Adjusting for Material
Characteristics
When the probe is covered with non-conductive bulk solid having a low
dielectric constant, then the Nivocompact only switches when the rod is
submerged in the material by several centimetres.
The degree of covering depends on the calibration.
Turning the fine calibrating element clockwise causes the Nivocompact to
become less sensitive.
Do not Forget!
•
Adjust the switching delay (refer to Page 19).
•
Select the safety switching required (refer to Page 20).
Fig. 18
The capacitance calibration must be carried
out both slowly and carefully.
Fig. 19
Accurate adjustment ensures high switching
reliability.
Material characteristics (bulk solid)
Very low dielectric constant
ε
r
approx. 1.6
…
2.0
No build-up approx. 180° (4 divisions)
With low build-up approx. 270° (6 divisions)
Low dielectric constant
ε
r
approx. 2.0
…
2.5
No build-up approx. 1 complete turn
With low build-up approx. 1
1
/
2
turns
Average dielectric constant
ε
r
approx. 2.5
…
4.0
No build-up approx. 1
1
/
2
turns
With low build-up approx. 2 turns
High dielectric constant or
conductive material No build-up approx. 2 turns
With low build-up approx. 4 turns
Nivocompact FTC 831 Calibration
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