wtw pHotoFlex, Operating Manual

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Lists pHotoFlex / pHotoFlex Turb
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Junction The junction is a porous body in the housing wall of reference elec-
trodes or electrolyte bridges. It forms the electrical contact between
two solutions and makes electrolyte exchange more difficult. The ex-
pression, junction, is also used for ground or junction-less transitions.
LED Light Emitting Diode
LEDs are used as the light source in the pHotoFlex (Turb).
Measured parameter The measured parameter is the physical dimension determined by
measuring, e. g. pH, conductivity or DO concentration.
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. meter and sensor. In addition, there is the cable and possibly an
amplifier, terminal strip and armature.
Method A method comprises a chemical detection procedure and special
method data (calibration line) that is required to evaluate the
measurement results.
How to carry out the method up to measuring with the photometer is
described in the analysis specification.
The pHotoFlex (Turb) contains a database with methods (programs).
Furthermore, user-defined methods can be entered in the database as
well.
Molality Molality is the quantity (in Mol) of a dissolved substance in 1000 g sol-
vent.
MultiCal
®
WTW name stating that a meter provides several pH calibration pro-
cedures.
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).
pH value The pH value 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.
Potentiometry Name of a measuring technique. The signal (depending on the mea-
sured parameter) of the electrode is the electrical potential. The elec-
trical current remains constant.