Schambeck SFD GmbH
Refractive Index Detector RI2000
SFD101.01.3x.EN / 2014-07-10
41
http://www.schambeck-sfd.com
Now the signal at the integrator output and the recorder output is exactly 0 mV. Press the
ENTER
button again to switch to the next voltage. The current voltage which is applied to
the signal output is shown in the display.
15.4 C
ALIBRATING THE
RI2000
The calibration mode of the RI2000 detector is used to calibrate the signal response to a
certain sample concentration. This step is needed if the instrument is used to perform
quantitative analysis. The detector is calibrated when shipped to the customer. Usually a
re-calibration has to be performed after modifications of the optical system only. Under
normal operation conditions a re-calibration of the RI2000 is not needed.
To calibrate the signal response of the instrument you need a
test standard solution
of
exactly
343 mg glucose in 100 mL distilled water
which is used as standard. The
refractive index of this solution is known and saved as an internal constant in the detectors
firmware.
The first step of the calibration is purging the reference chamber and the sample chamber
of the flow cell with distilled water. In the second step the sample chamber is filled with the
standard solution. At this point the theoretical detector signal is 500 mV. The real detector
signal is recognized by the firmware and the calibration factor to reach the theoretical
500 mV is calculated and saved as internal constant.
The correlation between the refractive index and the detector signal is:
1 mV
1 µRIU
