Delta OHM HD 8706-R1, Instruction Manual

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ENGLISH
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5.1 CONDUCTIVITY MEASUREMENT WITH
TWO-ELECTRODES PROBES
Two-electrodes probes with or without Pt100 temperature sensor and cell
constant K
≈
K 0.1, K 1, K 10 • cm -1 can be connected to the instrument -
input B. The measuring range of these cells is indicated in the diagram
which follows:
6 APPLICATIONS OF CONDUCTIVITY MEASUREMENTS
If must always be remembered that the conductivity of a liquid is propor-
tional to the total amount of dissolved substances and not to one specific
substance. Despite these there are many applications of conductivity,
especially for quality controls.
6.1 CHECKING IMPURITIES IN WATER
The most frequent applications are in the demineralization of water, by dis-
tillation, jonic exchange or inverse osmosis. Of course it is not possible to
measure impurities that do not contribute to conductivity, such as sand, oil,
micro-organisms, etc. Good distilled water should have a conductivity of
less than a few µS.
An interesting application is the determination of impurities in sugar. Sugar
is not an electrolyte and does not contribute to a variation of conductivity if
it is dissolved in demineralied water, but impurities do.
1 10 100 10 100 1000
µ S / cm mS / cm
0.1
K=10
K=1.0
K=0.1