VWR MD 8000 L, Руководство по эксплуатации

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MD 8000 L Conductivity
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9.1.2 Measuring the temperature
For reproducible conductivity measurements, it is essential to measure the
temperature of the test sample.
IDP sensors measure the temperature with a temperature sensor integrated in
the IDP sensor.
9.2 Temperature compensation
The calculation of the temperature compensation is based on the preset refer-
ence temperature, 20 °C or 25 °C. It appears on the display as
Tr20 or Tr25 .
You can select one of the following temperature compensation methods:
 Nonlinear temperature compensation ( nLF ) according to EN 27 888
 Linear temperature compensation (lin) with adjustable coefficients of
0.000 ... 3.000 %
/
K
 No temperature compensation (off)
Application tips Select the following temperature compensations given in the table according to
the respective test sample:
9.3 Calibration
9.3.1 Why calibrate?
Aging slightly changes the cell constant, e. g. due to coatings. As a result, an
inexact measured value is displayed. The original characteristics of the cell can
often be restored by cleaning the cell. Calibration determines the current value
The reference temperature and temperature compensation are set
in the menu for the parameter, conductivity (see section 11.4.1
S
ETTINGS FOR
IDP
CONDUCTIVITY SENSORS
, page 66).
Test sample Temperature compensation Display
Natural water
(ground water, surface
water, drinking water) nLF
according to EN 27 888
nLF
Ultrapure water nLF
according to EN 27 888
nLF
Other aqueous solu-
tions Lin Set linear
temperature coefficient
0.000 ... 10.000 %/K
Lin
Salinity (seawater) Automatic nLF according to
IOT (International Oceano-
graphic Tables)
Sal , nLF