wtw Cond 7310, Руководство по эксплуатации

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Cond 7310 Glossary
ba75933e04 06/2013
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14 Glossary
Conductivity
General information
Cell constant C Characteristic quantity of a conductivity measuring cell, depending on
the geometry.
Conductivity Short form of the expression, specific electrical conductivity.
It corresponds to the reciprocal value of the resistivity.
It is a measured value of the ability of a substance to conduct an electric
current. In water analysis, the electrical conductivity is a dimension for
the ionized substances in a solution.
Reference tempera-
ture
Fixed temperature value to compare temperature-dependent measured
values. For conductivity measurements, the measured value is con-
verted to a conductivity value at a reference temperature of 20 °C or 25
°C.
Resistance Short name for the electrolytic resistivity. It corresponds to the recipro-
cal value of the electrical conductivity.
Salinity The absolute salinity S
A
of seawater corresponds to the relationship of
the mass of dissolved salts to the mass of the solution (in g/Kg). In prac-
tice, this dimension cannot be measured directly. Therefore, the practi-
cal salinity according to IOT is used for oceanographic monitoring. It is
determined by measuring the electrical conductivity.
Salt content General designation for the quantity of salt dissolved in water.
Temperature coeffi-
cient
Value of the slope of a linear temperature function.
Temperature compen-
sation
Name of a function that considers the temperature influence on the
measurement and converts it accordingly. Depending on the measured
parameter to be determined, the temperature compensation functions
in different ways. For conductimetric measurements, the measured
value is converted to a defined reference temperature. For potentiomet-
ric measurements, the slope value is adjusted to the temperature of the
test sample but the measured value is not converted.
α
T
Ref
=
Meas
*
1
1 +
a (T - )
*
T
Ref
Adjusting To manipulate a measuring system so that the relevant value (e. g. the
displayed value) differs as little as possible from the correct value or a
value that is regarded as correct, or that the difference remains within
the tolerance.
AutoRange Name of the automatic selection of the measuring range.
Calibration Comparing the value from a measuring system (e. g. the displayed
value) to the correct value or a value that is regarded as correct. Often,
this expression is also used when the measuring system is adjusted at
the same time (see adjusting).