Design And Function - WIKA OLS-C Series 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.
WIKA operating instructions optoelectronic level switches, models OLS-C
Operating principle
Gas
Liquid
EN
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