Description
Dissolved oxygen sensors
The measured variable “dissolved oxygen” indicates the amount of gaseous oxygen physically dissolved in the aqueous phase in mg/l (ppm) or the oxygen saturation of the water in %. The new DO3 type is based on optical fluorescence measurements and can be connected to the process with dip tubes or flow tubes. It can be used to control more oxygen-rich water, such as surface water and drinking water, and to regulate the aeration of activation tanks in treatment plants.
Applications
- Wastewater treatment: optimizes the oxygen input in the activation tank of water treatment plants, which helps to save energy.
- Fish farming: regulates the entry of oxygen into waters to be conditioned for animal husbandry
- Drinking water supply: aeration optimization in water supply plants
- Environmental engineering: assessment of surface water quality
Technical information
- Measuring accuracy: OD type 2: ±0.05 mg/l , OD type 3: ±0.1 mg/l
- Temperature: 0 – 50 °C
- Max. pressure: DO 2 type: 1 bar , DO 3 type: 2 bar
- Type of protection: IP 68
- Supply voltage: Type DO 2: 12 … 30 V DC, type DO 3: 18 … 30 V DC
DO 3-mA dissolved oxygen sensor
Magnitude of measurement |
Dissolved oxygen |
Calibration |
In air oxygen or by reference measurement in process water |
Measurement Accuracy |
±0.1 mg/l |
Reaction time as t 90 |
|
Temperature |
0 … 50 °C |
Temperature correction |
Pt1000 integrated, externally driven |
Max. pressure |
2.0 bar |
Flow rate |
Measurement possible even without flow rate |
Supply voltage |
18…30 VCD |
Electrical connection |
fixed cable 10 m |
Output signal |
4…20 mA associated with the measuring range, temperature-corrected, calibrated and galvanically separated |
Type of protection |
IP 68 |
Installation |
a) Immersion by means of immersion pipe (PVC, d40/ DN 32, provided by the customer). The connection can be made using the dip tube adapter (reducing nipple, Cat. No. 356924) and the 45° elbow (Cat. No. 356335). Both components are included in the standard package and can be ordered as accessories (see also the accessories section).
b) Installation on the ProMinent bypass fitting, type DGMa with mounting kit 791818 and type DLG III with mounting kit 815079 |
Measuring and control instruments |
DACb from firmware 02.01.01.02 with full calibration functionality and all correction quantities (temperature, salinity, atmospheric pressure, height above sea level). Units displayed:[ppm] and [% oxygen saturation]. DACa, AEGIS II, D1C:calibration only with introduction of a reference concentration determined from the process water. Temperature correction magnitude only. Unit displayed: [ppm] |
Typical Application |
Control of oxygen inlet to the activation tank (treatment plant), control of oxygen inlet in water supply plants, fish and shrimp farms, water conditioning of large aquariums in zoos, evaluation of the biological state of surface waters. |
Resistant to |
Dirty water and the following chemical compounds: carbon dioxide, hydrogen sulfide, sulfur dioxide, ethylene oxide, and gamma ray sterilization. |
Disturbance from |
Oxidizers (e.g., chlorine, chlorine dioxide, ozone) and some organic solvents, (e.g., chloroform, toluene and acetone) |
Measuring principle, technology |
Optical: Measurement of the time it takes for pulses of fluorescent radiation to return |
DO 2-mA dissolved oxygen sensor
Magnitude of measurement |
Dissolved oxygen |
Calibration |
in oxygen in the air or by reference measurement in the process water |
Measurement Accuracy |
±0.05 mg/l |
Reaction time as t 90 |
22 s |
Temperature |
0 … 50 °C |
Temperature correction |
– |
Max. pressure |
1.0 bar |
Flow rate |
minimum 0.05 m/s |
Supply voltage |
12…30 VCD |
Electrical connection |
fixed cable 10 m |
Output signal |
4…20 mA Calibrated, temperature-corrected and galvanically isolated measuring range |
Type of protection |
IP 68 |
Installation |
Floating ball with venturi grooves to increase flow for self-cleaning of the sensor part.
Delivery includes the adapter for connection to PVC pipes with outer diameter: 50 mm and the rail bracket also for PVC pipes with outer diameter: 50 mm (see accessories). The customer must install the straight PVC pipe and a standard 45º elbow to be glued with the PVC pipes (outer diameter 50 mm). |
Measuring and control instruments |
D1C, DAC |
Typical Application |
Control of oxygen inlet in the activation tank (treatment plant). |
Resistant to |
Dirty water |
Disturbance from |
Oxidants (e.g., chlorine, chlorine dioxide, ozone) and some organic solvents (e.g., chloroform, toluene and acetone), as well as hydrogen sulfide. |
Measuring principle, technology |
amperometric, 2 electrodes, with diaphragm, encapsulated and integrated floating ball measuring value recorder |