OPT
OPT K02/0410
Page 3
3. Instrument Inspection
All Instruments are inspected before shipping and sent out in perfect condition.
Should damage to a device be visible, we recommend a thorough inspection of
the delivery packaging. In case of damage, please inform your parcel service /
forwarding agent immediately, since they are responsible for damages during
transit.
Scope of delivery:
The standard delivery includes:
•
Optical Level Sensor
model: OPT
•
Operating instructions
4. Regulation Use
Any use of the Optical Level Sensor, model: OPT, which exceeds the
manufacturers specification may invalidate its warranty. Therefore any resulting
damage is not the responsibility of the manufacturer. The user assumes all risk
for such usage.
5. Operating Principle
The optical level sensors of model OPT have been developed for monitoring
transparent
liquids. Due to the very small dimensions, very slight switching
hysteresis and high repeatability, the instruments are also suited for service in
small vessels. The optical sensor is situated in a robust housing. It comprises a
plastic hollow hemisphere, in which the infrared diode is fitted as a transmitter
and a semiconductor as a receiver. When the sensor is not wetted by liquid, the
infrared light is reflected fully from the surface of the hemisphere to the receiver.
As soon as the sensor is covered with liquid, the refractive index on the boundary
layer changes and most of the light escapes into the liquid. Less light then
reaches the receiver, which allows switching to take place. The level probe
should not be fitted with the sensor pointing downwards, as errors can occur due
to drops of liquid sticking to it.
