ChromeGate 3.3.2 Software Manual - KNAUER Advanced Scientific ...

108 Creating an Instrument Control Method
Fig. 160 ASM 2.1L setup window for pump, valve, detector
Run time
Run time determines the run time of all devices of the Assistant.
Acquisition delay (only for UVD2.1S)
Acquisition delay is the interval between the start of the run (Trigger) and
the time when sampling starts for this detector. This option will only be
shown, if a detector is configured in the ASM 2.1L.
UV (only for UVD2.1S)
This section only appears, if the detector UVD2.1S is configured.
Time Constant
Select the time constant for the detector from the drop-down list. The
values are 0.1, 0.2, 0.5, 1.0, 2.0, 5.0, and 10.0 sec. The additional
values 0.000, 0.005, 0.01, 0.02, 0.05 will only be available, if the
detector is connected by LAN. Smaller time constants are required for
high speed analyses. A good rule is to select a time constant, which is
the reciprocal of the data rate in Hz (e.g. 2 Hz data rate -> 0.5 sec
time constant).
Sampling rate
The sampling rate is the rate at which data will be sampled by the
system. Click on the down-arrow to get a list of the frequencies
available for the configuration of your system. The choices are: 1, 2, 5,
and 10 Hz and, if the detector is connected by LAN, also 20, 50 and
80 Hz. For any selected sampling rate the narrowest peak width will
be shown, for which this sampling rate will be adequate. This selection
is in Hz (data points per second). This is the selection for most
chromatography applications. We recommend having more than 20
data points per peak (30 – 40). This means that for a peak with a peak
width of 20 seconds (from peak start to peak end) a data rate of 2 Hz
is recommended.
Autozero at start
Check the Autozero field if you wish the signal to be zeroed at the
moment a measurement is started (to define the current signal as the
baseline).