Waters 2489, Operator'S Manual

Page: 23 / 234

Principles of operation 1-7
Comparison of flow cell characteristics
The standard analytical, inert, and LC/MS cells have a path length of 10 mm.
The semi-prep and microbore cell path length is 3 mm. The autopurification
cell path length is 1.0 mm. A variable path length flow cell (path length 0.15 to
3 mm) is also available.
Filtering noise
The detector provides a Hamming filter to minimize noise. The Hamming
filter is a digital finite impulse response filter, which creates peak height
degradation and enhances the filtering of high frequency noise.
The behavior of the filter depends on the filter time constant you select. You
can program a filter time to be Fast, Slow, Normal, or Other. If you select
Fast, Slow, or Normal, you do not need to enter a value. The filter constant is
determined by the data rate. If you select Other, you can enter a value.
However, the value you enter will be rounded up or down to a value based on
the data rate.
Conventional Cell
TP01530
Waters TaperSlit™
Analytical Cell
UV
Light
Window
Window
UV
Light
Lens
Window