KROHNE OPTISENS AAS 2000 EN - Manual (Page 34)

7
TECHNICAL DATA
34
OPTISENS AAS 2000
www.krohne.com 12/2008 • MA AAS 2000 R01 en
Technical data
7.1 Measuring principle
The electrode is a Clark type electrode with a membrane in FEP. The sensor consists of a gold
cathode and silver anode. The Clark cell detects the oxygen though its reduction at the gold
electrode. A membrane covers the two electrodes and blocks access of most species to the
electrodes. Only dissolved gases such as oxygen can traverse the membrane, hence the
reduction current responds to the oxygen concentration.
The electrode housing is made of PVC and is equipped with an O-ring sealing against the
mounting. There is a connector on the electrode for the amplifier cable.
Active components included in the electrode are treated to maximize their life span.
In addition, the temperature is measured to be used for temperature compensation of the
measured value. It can be read in the converter and used as secondary value when a sensor is
configured to use both analog outputs.
7.2 Technical data
INFORMATION!
The build in temperature measurement is not a precision measurement, but shall be seen as an
indication.
Measuring system
Measuring principle Amperometric measuring principle with a
"Clark" electrode
Application range Continuous measurement of dissolved oxygen
in water (here especially in waste water
applications), e.g. in aeration basins
Modular design A typical measuring system consists of:
MAC 080 multiparameter converter
1 (or up to 4) OPTISENS 2000 sensors
Solenoid valves to control spray cleaning
Assemblies for submersion or side wall
installation
Measuring range 0…20 mg/l (ppm)
Measuring accuracy ±1% FS (full scale)
Operating conditions
Temperature range 0…+50°C / 32…122°F
Max. immersion depth 10 m / 32.8 ft
Calibration Software-support zero point calibration and
single point calibration by calibration
measurement in air
.book Page 34 Monday, December 15, 2008 12:43 PM