wtw inoLab 740, Operating Manual

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Lists
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Measured value The measured value is the special value of a measured
parameter to be determined. It is given as a combination
of the numerical value and unit (e. g. 3 m; 0.5 s; 5.2 A;
373.15 K).
Measuring system The measuring system comprises all the devices used for
measuring, e. g. measuring instrument and probe. In
addition, there is the cable and possibly an amplifier,
terminal strip and armature.
Molality Molality is the quantity (in Mol) of a dissolved substance in
1000 g solvent.
MultiCal
®
WTW name stating that a measuring instrument provides
several calibration procedures.
Offset potential The measurable potential of a symmetrical electrode, the
membrane of which is immersed in a solution with the pH
of the nominal electrode zero point. The asymmetry is part
of the offset potential.
ORP voltage The ORP is caused by oxidizing or reducing substances
dissolved in water if these substances become effective
on an electrode surface (e. g. a gold or platinum surface).
OxiCal
®
WTW name for a procedure to calibrate D. O. measuring
systems in water vapor saturated air.
Oxygen partial pressure Pressure caused by the oxygen in a gas mixture or liquid.
Oxygen saturation Short name for the relative D. O. saturation.
Note: The D. O. saturation value of air-saturated water and
the D. O. saturation value of oxygen-saturated water are
different.
pH value The pH is a measure of the acidic or basic effect of an
aqueous solution. It corresponds to the negative decadic
logarithm of the molal hydrogen ions activity divided by the
unit of the molality. The practical pH value is the value of
a pH measurement.