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2 determining delta t, Determining delta t – Metrohm 743 Rancimat User Manual

Page 58

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4.4 Calibration functions

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50

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743 Rancimat

Enter the conductivity of the standard used.

c(KCl) = 1 mmol/L can be used as a standard solution. This is
derived from the optionally available conductivity standard
6.2301.060 (KCl 0.1 mol/L) through dilution with distilled water. The
conductivity of this diluted solution is:

Temperature Conductivity

18 °C

19 °C

20 °C

21 °C

22 °C

23 °C

24 °C

25 °C

127 µS/cm

130 µS/cm

133 µS/cm

136 µS/cm

138 µS/cm

141 µS/cm

144 µS/cm

147 µS/cm

Alternatively, the conductivity standard 6.2324.000 (undiluted) can
be used.

3 Start determination and check the values

Click on [Start] to start the determination of the cell constant.

After the determination is finished, the dialog window Enter/Check
cell constants
appears again.

If you wish to accept the displayed values, click [OK].

If you wish to maintain the old values, click [Cancel].

4.4.2

Determining Delta T

The temperature correction Delta T indicates the deviation of the cur-
rent temperature of the sample from the temperature in the heating block
and belongs to the method as a parameter (see Chapter 4.5.2, page
60)
. It can automatically be determined with the calibrated, external tem-
perature sensor (part of the optionally available GLP test set, see Optional
accessories, page 185
).