Waters 2489, Руководство оператора

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Operational modes 1-15
RatioPlot
The detector allows ratio plotting: comparing the absorbances of a compound
or analyte at two different wavelengths. The RatioPlot divides absorbances at
two selected wavelengths and plots the resulting ratio on a chart recorder or
data system over one output channel (channel A). The RatioPlot is useful in
detecting hidden components present within individual peaks.
The RatioPlot of a spectrally homogeneous peak appears as a rectangular
wave. The RatioPlot of an impure peak appears as a distorted wave. When
obtaining a RatioPlot, you must be operating the detector in dual wavelength
mode; the RatioPlot is output on the selected channel.
For an explanation of the RatioPlot procedure, see the discussion “Obtaining a
RatioPlot” on page 3-34 .
MaxPlot
The MaxPlot function monitors absorbance at two selected wavelengths and
plots the maximum absorbance value for each sample component. To obtain a
MaxPlot, you must operate the detector in dual wavelength mode. The
MaxPlot outputs the greater of the two absorbance values on the selected
channel.
For an explanation of the MaxPlot procedure, see the discussion “Obtaining a
MaxPlot” on page 3-35 .
Thermal wander management
To mitigate thermal instability caused by ambient temperature changes, the
detector has improved insulation (for better air flow across the optics bench)
and a variable speed fan that will run at higher or lower speeds as needed.
You will hear the fan change speeds in response to the thermal changes. This
is normal operating behavior.