Product Description; General Information; Principle - Mettler Toledo InPro 6000 Bedienungsanleitung

InPro 6000 Series Optical O
3

Product description

3.1

General information

The optical oxygen sensors with integrated tempera-
ture probe are used for meas ure ment of oxygen.
The sensors are sterilizable and compatible with CIP
(cleaning in place). The sensor InPro 6860 i is also
autoclavable (max. 284 °F).
3.2

Principle

The optical oxygen sensors are based on an optical
detection method, the so called fluorescence quenching.
Here is a short summary of the principle. In contrast to
the polarographic Clark-electrode, which detects a redox
reaction of oxygen at the electrode, the optical method
is based on an energy transfer between a chromophore
and oxygen.
– A chromophore, embedded in the sensor tip is illumi-
nated with blue light. This chromophore absorbs the
energy and if no oxygen is present emits red fluores-
cence light with a specific lifetime. This emitted light
is being detected by a detector in the sensor head.
– In the presence of oxygen, the chromophore transfers
the energy to the oxygen molecule. Oxygen is then
able to transfer this energy as heat to the surrounding
area and no fluorescence is emitted.
– The total intensity of the fluorescence and the lifetime
of the fluorescence is related to the Oxygen partial
pressure in the medium.
– To analyze the lifetime of the fluorescence, the ex-
citation light is pulsed with a constant frequency,
the emitted light shows the same course but with
a time delay to the excitation. This delay is called
Phase shift or Phase angle (Phi). The phase shift is
dependent on the oxygen level and follows the Stern-
Vollmer correlation.
– The sensor detects this phase shift and calculates the
oxygen concentration.
– The oxygen value ist digitally transferred to the
transmitter.
© 01/ 2016 Mettler-Toledo GmbH InPro 6000 optical O
Printed in Switzerland
Sensors 12 mm
2
11
sensors
2
52 206 256