Design And Function - WIKA OLS-C20 Operating Instructions Manual

2. Design and function

2. Design and function
2.1 Description
This instrument is used for the detection
of limit levels in liquids. The measuring
principle is independent of refractive
index, colour, density, conductivity and
dielectric constant. The switches consist
of an infrared LED and a phototransistor.
The light of the LED is directed into a
prism. So long as the sensor tip of the
prism is in the gas phase, the light is
reflected within the prism to the receiver.
When the liquid in the vessel rises and
wets the glass tip, the infrared lightbeam
into the liquid is interrupted and only a
small portion reaches the receiver.
The integrated switch electronics offer an automatic adjustment so
that there is a wide field of application. For the output, there is an O.C.
pnp-transistor switching output or a relay switching output.
2.2 Instrument construction
Depending on the switch type, the instruments are fitted with different
process connections. These contain a glass prism and the electronics
responsible for the evaluation.
Operating instructions model OLS-C20
Operating principle
Gas
Liquid
EN
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