Level measurement
KS 98 application
Measurement of filling level in tanks
with irregular cross section
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Description
On tanks with irregular cross section over
the height, the volume is not proportional
to the filling level. Therefore, the tank
contents cannot be measured directly, but
can be calculated from the level signal
provided from a wide range of sensors.
The most common types are: immersion
sensors, resistive sensors, pressure
sensors, radar, ultrasonic and microwave
measurement, as well as float switches.
With a non-linear relationship between
filling level and volume, the correlation for
rotationally symmetrical vessels (spherical,
elliptical, conical, etc.) can be calculated.
However, in spite of very precise computed
results, deviations from the theoretical
volume can occur, e.g. as caused by slight
deformations of the vessel’s walls and/or
through small deviations from the perpendicular
(except with spherical tanks).
Therefore, it can be advisable to use a
configurable linearization curve when calculating
the volume of irregularly shaped
tanks.
Copyright © 2005 PMA Prozeß- und Maschinen-Automation GmbH
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