User manual

60 1200 Series Variable Wavelength Detector User Manual
4Using the Detector
Special Setpoints
1 To change the offset and the attenuation select VWD Signal - More - Special
Setpoints.
Figure 24 Spectra Window
Margin for negative Absorbance:
Use this field to modify the
detector’s signal handling to
increase the margin for negative
absorbance. Use this option if, for
example, your solvent gradient
produces a decreasing baseline
absorbance, and for GPC analyses.
Limits: 100 to 4000 mAU.
Signal Polarity: can be switched to
negative (if required).
Enable analysis when lamp is off: if
the VWD is not used in a dual
detector setup (lamp off), the
not-ready condition is not stopping
the analysis.
Scan Range / Step: Used for
stop-flow scanning, see “Scanning
with the VWD" on page 57.
NOTE
Margin for negative Absorbance: The higher the value the greater the baseline noise. Set
this value only if you expect negative absorbance greater than -100 mAU.