Salinity Correction; Ambient Pressure During Dissolved Oxygen Measurement; Conductivity; Measuring Ranges And Cell Constants - Lovibond Tintometer SD 335 Multi Bedienungsanleitung

6.5 Salinity correction

As the salinity (salt content) increases, the solubility of oxygen in the water decreases, i.e.
fewer mg of oxygen are dissolved per litre of water at the same partial pressure of oxygen.
To determine this oxygen concentration, the salinity of the medium must first be entered
into the configuration menu. The salinity correction is adapted to aqueous media that have a
chemical composition equivalent to seawater. The International Oceanographic Tables (IOT)
are used as the basis for the salinity correction.

6.6 Ambient pressure during dissolved oxygen measurement

The air pressure ratios at the place of measurement play a major role in:
• The calculation of the O
• The calculation of the O
• The evaluation of the calibration
An integrated air pressure sensor is used to continuously measure the ambient pressure and
compensate it for the calculation.

7 Conductivity

7.1 Measuring ranges and cell constants

Depending on the type of electrode, different measuring ranges are accessible depending on
the cell constant K. The cell constant of the measuring cell must be entered in the parameter
configuration for conductivity before use. Information regarding factory-tested cell constants
can be found in the test log or on the cable tag on the electrode.
Conductivity measuring
cell
LC 12
LC 16
Alternatively, the cell constant can be determined via calibration either using the automatic
recognition of a standard reference solution or the manual entry of a known conduction value.
SD_335_1 06/2020
saturation (% O )
2 2
concentration (ppm, mg/litre)
2
Cell constant
ca. 0,55 cm
ca. 0.42 cm
Measuring range
< 200 mS/cm
-1
< 1000 mS/cm
-1
55