24 Operation
AZURA® Conductivity Monitor CM 2.1S Instructions, V6710
Process
Display
1.
Press both arrow keys.
2.
Hold down the left arrow key and use the right
arrow key to scroll until the correct display
appears.
3.
Let go of the arrow keys and press the left or
right arrow key to select an option.
Check if the conductivity monitor appears in the software.
5.4 Checking the operating hours
The operating hours of the monitor can be viewed in the GLP menu,
which dis plays the value in hours according to GLP specifications.
The monitor has been switched on.
Process
Display
1.
Press both arrow keys.
2.
Hold down the left arrow key and use the right
arrow key to scroll until the correct display
appears.
3.
Let go of the arrow keys.
Enter additional settings or start the analysis.
5.5 Activating/setting the temperature
compensation
The conductivity of aqueous solutions increases with higher temperatures
(by about 1.6 to 2.2 % per Kelvin, depending on the type of dissolved
salt), so the conductivity of an electrolyte solution must always be speci-
fied to a temperature. For example, the specific conductivity for a pH-neu-
tral 1 M NaCL solution at 25 °C is about 86.6 mS/cm - at 26 °C about
88.1 mS/cm.
Depending on the experimental problem, the CM 2.1S can either display
the actual measured value (raw data) for conductivity or convert these
values to theoretical values at a specified temperature. This temperature
is called the reference temperature (
TEMP-REF). The process is called tem-
perature compensation.
For this purpose, the CM 2.1S permanently records the temperature of
the medium flowing through the cell with the aid of a temperature sensor
implemented in the flow cell.
By entering a correction factor (
TEMP-COR) in percent, you activate the
temperature compensation. Since this correction factor is substance-
specific, KNAUER recommends setting it to 1.7 % when dealing with
FPLC-compatible electrolyte and buffer solutions.
Next steps
Prerequisites
Next steps
Operating principle
