2 determining delta t, Determining delta t – Metrohm 873 Biodiesel Rancimat Manual User Manual
Page 58

4.4 Calibration functions
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873 Biodiesel Rancimat
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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
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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 current
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 temperature
sensor (part of the optionally available GLP test set, see Optional accesso-
ries, page 180).