Thermo Scientific 074114, Руководство оператора

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5.5 Replacing the Flow Cell Windows
Contaminated flow cell windows can significantly increase baseline noise and
cause wavelength calibration to fail. If cleaning the cell (see
Section 5.2 ) does
not eliminate these problems, replace both windows.
NOTE The windows in the semi-preparative flow cell cannot be
replaced. If cleaning the windows does not eliminate the
problems described above, order a new semi-
preparative cell.
The Dionex AD25/Dionex PDA/Dionex PDA-100 Flow Cell Windows
Replacement Kit (P/N 060498) contains all of the parts required to replace the
fused silica windows in a standard or semi-micro cell. The kit is optional and must
be ordered separately from the Dionex PDA.
1. Remove the flow cell from the optical bench (see
Section 5.4 ) and place the
cell on a clean work surface.
2. Disassembling the cell with bare hands may introduce contaminants into the
system. Before proceeding, put on a pair of latex gloves that are lint-free,
particle-free, and oil-free.
3. Using the windows replacement tool (P/N 060497), remove one of the flow
cell retaining nuts from the cell (see Figure 5-2 ). (It does not matter which
retaining nut is removed first.)
4. Remove and discard the old window.
5. Use tweezers to carefully remove the O-ring from the groove (see Figure 5-2 ).
Do not scratch the groove.
Even minute particles of dust, dirt, etc. on the flow cell parts can
contaminate the cell and result in excessive baseline noise and drift.
The following factors will prevent the new O-ring from sealing
properly and will cause leaks: scratches in the groove, particles of
dust or dirt in the groove, and failure to seat the new O-ring in the
groove.