Measuring Samples - Knauer K-7400 Benutzerhandbuch

Using the Osmometer K-7400

Measuring Samples

SOP 4
new value will be abandoned and the CALIBRATE menu will be
shown again.
5. Wait for the warming up to the stand-by temperature.
6. Prepare the instrument according SOP 1 for a measurement of a
400 mOsm/kg calibration solution (KNAUER Order No. Y1241).
7. Activate the second calibration field and select "0400" and repeat
steps 3 to 5.
If for special applications as some times in the pharmaceutical industry a
3 point calibration is required proceed according SOP 3 and repeat the
procedure for calibration field 3.
A new calibration is also necessary after
1. exchanging the measurement head
2. changing the settings of FREEZING potentiometer
Performing a Sample Measurement
1. Prepare the instrument according SOP 1 for a measurement of a
sample solution.
2. Press the START key to start the measurement run. While running
the screen displays the sample temperature and the elapsed time.
RUN >
At any time the run can be interrupted pressing the STOP key.
3. The instrument detects the freezing point depression and if the
crystallisation occurred
osmolality. On the main screen.
>>> 1234 mOsmol <<<
♦ <next sample>
4. The printer output is given in the format
Measured 1234 mOsmol/kg
19.03.15 16:05:35
If no crystallisation (temperature increase) takes place after the
automatically start of the vibrator the measurement will be stopped
with the error message
> ERROR <
NO FREEZE
If the crystallisation (temperature increase) takes place before the
start of the vibrator the measurement also will be stopped with an
error message
-1.23°C<
01:23
properly displays
15
the corresponding