Knauer Azura DAD 2.1L Benutzerhandbuch Seite 39

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interfering with integration, the time constant should be
increased. If resolution is compromised, it should be decreased.
It is recommended to set the time constant and data rate in rela-
tion to peak width.
Data rate The data rate (or sampling rate) is the number of data points per
second (Hz) at which the detector transmits data to the com-
puter.
Default data rate The default data rate setting for the detectors is 1 Hz (see "Re-
Setting the Device" on page 34). The maximum data rate (digi-
tal signal) is 100 Hz. Slower data rates store average data points.
A 50 Hz data rate averages 2 points. A 10 Hz data rate averages
10 points. The analog data rate is fixed at 12.5 Hz.
Optimizing the The optimal data rate depends on your application. Too few
data rate points across a peak (short data rate) decrease detail and com-
promise reproducibility. Too many points (high data rate) intro-
duce noise into the system and the resulting files can become
very large. Some general considerations are listed below:



If the data rate is too slow, the start and end points of the peaks
are not accurately determined. If the data rate is too fast, data
KNAUER
Optimizing the Detector
Peak width Time constant
[min] [s]
<0.003 0.01
>0.007 0.02
>0.017 0.05
>0.033 0.1
>0.067 0.2
>0.167 0.5
>0.333 1
Each peak should be defined by 20–30 data points. For chro-
matograms with co-eluting peaks or low signal-to-noise
ratios, 40–50 data points per peak are recommended.
If all peaks are relatively wide, select a slower data rate.
If any peaks of interest are less than a few seconds, select a
faster data rate.
DAD 6.1L, DAD 2.1L, MWD 2.1L User Manual V6700, Version 1.0
Data rate
[Hz]
100
50
20
10
5
2
1