Yokogawa EXAxt SC450 4-Wire Analyzer for Conductivity/Resistivity - Manual (Page 56)

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IM 12D08N05-01E
Checking
When the temperature coefficient already set is accurate, the conductivity to be displayed must be
constant regardless of liquid temperature. The following check will make sure that the temperature
coefficient already set is accurate.
If, when the liquid temperature is lowered, a larger conductivity value is indicated, the temperature
coefficient already set is too small.
The opposite also applies. If a smaller conductivity value is indicated, the temperature coefficient
already set is too large. In either case, change the temperature coefficient so that the conductivity
no longer changes.
Matrix compensation
The compensation matrix is a table of temperature and conductivity values at differing concentra-
tions. These values are used to calculate the temperature compensation applicable for a particular
solution. Choose the component that you will be measuring in your application, and where appro-
priate the concentration range. The EXAxt will do the rest.
By following the routing:
Commissioning>> Measurement setup>> Temp.compensation>> Matrix
you gain access to the Matrix selection area.
Matrices are available for the common mineral acids and bases. In addition Ammonia and Morpho-
line are included. In short by using the matrix method, specialist compensation is available for the
majority of applications in the power industry, water treatment, and chemical manufacturing. The
following matrices are available initially, but as with all Yokogawa products, we are continually striv-
ing to improve both the quality and technological content. Further solutions will be added to this list.
Ammonia 0..50 ppb 0..90˚C
Ammonia 15..30% 10..50˚C
Morpholine 0..500 ppb 0..90˚C
H
2
SO
4
0..27% 0..100˚C
H
2
SO
4
39..85% -18..116˚C
H
2
SO
4
93..100% 10..90˚C
NaOH 0..15% 0..100˚C
NaOH 25..50% 0..80˚C
HCl 0..200 ppb 0..100˚C
HCI 0..18% -10..65˚C
HCI 24..44% -20..65˚C
HNO
3
0..25% 0..80˚C
HNO
3
35..80% -16-60˚C