1100 Series DAD and MWD User Manual 101
How to optimize the Detector 5
Margin for Negative Absorbance
The detector adjusts its gain during balance such that the baseline may drift
slightly negative (about -100 mAU). In some special case, for example, when
gradient with absorbing solvents are used, the baseline may drift to more
negative values.
Only for such cases, increase the margin for negative absorbance to avoid
overflow of the analog-to-digital converter.