Conductivity/Tds/Salinity Measurement; Dissolved Oxygen Measurement - Consort C1020 Anleitung

Conductivity/TDS/Salinity measurement

Dissolved oxygen measurement

Conductivity measurement
1. Select the desired mode (S/cm) by pressing MODE. The display will
immediately show the measured value according to the previous calibration.
Should you want to recalibrate, press CAL.
2. The instrument permits to choose between the standards in memory (0.01,
0.1, 1 M KCl). Select the proper values and press CAL. The unused standards
should be switched off.
3. After rinsing the electrode several times with the first standard solution,
immerse it in that standard. The solution temperature is not so critical but
should lie between 0°C and 40°C. When no Pt1000 is used, do not forget to
compensate manually first! Select [CALIBRATE], press CAL and follow the
instructions on the screen until the calibration is finished.
4. Rinse the electrode several times with the sample, immerse it in that solution
and read the display.
5. Rinse the electrode always after use and store it in distilled water (add some
detergent to keep the spongy platinum surface in perfect condition).
TDS measurement
1. Select the desired mode (mg/l)(TDS) by pressing MODE. The display will
immediately show the measured value.
Salinity measurement
1. Select the desired mode (SAL) by pressing MODE. The display will
immediately show the measured value.
Dissolved oxygen measurement
1. Select [O ] by pressing MODE. The display will immediately show the
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measured value according to the previous calibration. Should you want to
recalibrate, press CAL.
2. The display shows the air pressure correction and the salinity correction.
Select the proper values and press CAL. Leave salinity correction to zero
unless you are going to measure in heavily salted solutions such as e.g. sea-
water (35 g/l). Select [CALIBRATE], press CAL and follow the instructions on
the screen until the calibration is finished.
3. The electrode exposed to the air reaches an equilibrium corresponding to the
partial pressure of oxygen and thus to saturation in water at the given
temperature. The instrument shows the measured saturation, current,
temperature, and will calibrate automatically when readings are stable.
4. After rinsing the electrodes with distilled water, immerse them in the samples
and read the display. Stirring the solution during the measurements promotes
the homogeneity and is obligatory! The advection rate must be at least 10
cm/s.
5. Rinse the electrode always after use and store it in distilled water.
Interferences
All substances which can diffuse through the membrane and for which 800 mV
potential suffices for polarographic reduction, will be reduced in the electrode.
This will give a corresponding current contribution, if they are present.
Interference can be caused by ions entering the electrode through porous or
mechanically damaged membranes and by diffusion of other reactive gases apart
from oxygen, e.g. CO
manner with the electrode. Acidic or basic gases change the pH value of the
electrolyte solution and thus disturb the reading, particularly when measuring
small oxygen concentrations. High salt concentrations in the sample solution can
falsify readings too.
(C1020 only)
(C1020 only)
, Cl , SO , and H S. These substances react in undesired
2 2 2 2
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