7 Reference
7.1 Conductivity measurement
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HORIBA
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Temperature compensation
The conductivity of a solution generally varies greatly,
depending on the temperature of the solution. Because
the conductivity of a solution is based on its ION
conductivity, as explained above, the higher the
temperature of the solution the more active its ions and
the higher its conductivity. Using a given temperature as
the standard (and calling that the standard temperature),
the “temperature coefficient” expresses how much
change (expressed in %) occurs in conductivity when
the temperature of the solution changes by 1ºC. The
temperature coefficient is expressed in units of “%/ºC
(standard temperature).” This temperature coefficient is
found by assuming that the conductivity of the sample
changes linearly in relation to temperature, whereas the
change in conductivity of an actual sample, strictly
speaking, follows a curve. The shape of this curve
changes, depending on the kind of sample being
measured. Most solutions, however, are said to
generally have a temperature coefficient of 2%/ºC (25ºC
standard), within a range where the size of the
temperature change is not very large.
The meter is equipped with a built-in automatic
temperature conversion function, enabling them to
automatically calculate and display, based on the actual
temperature measurement, the conductivity of a sample
at 25ºC, using a temperature coefficient of 2%/ºC.
