33
Maintenance and Care
KNAUER
10D User Manual V7670, Version 2.3
Users may perform the following maintenance tasks themselves:
Regularly check the operating hours of the deuterium lamp.
According to Good Laboratory Practice (GLP), a deuterium
lamp is to be in operation for no longer than 2000 operating
hours.
Inspect the flow cell assembly.
Clean the flow cell.
Replace the flow cell.
Replace the fiber optic connectors (Fiber Optics Version
only).
Order numbers of the required spare parts can be found in the
chapter
Accessories and Spare Parts
.
Cleaning the Flow Cell
Increased baseline noise and reduced sensitivity can be a result
of a dirty flow cell. Often it is sufficient to rinse the flow cell to
restore optimal sensitivity.
Note
Dirty lenses or fiber optic connectors could falsify the measure-
ment. Do not touch the lens or the fiber optic connector lends
with bare hands. Wear gloves.
Rinsing the Flow Cell
CAUTION!
Contamination of the flow cell caused by oil
drops! Do not use compressed air for drying.
Flushing solution:
The following solvents are recommended for flushing:
HCl
NaOH
Ethanol
Acetone
Tools
Syringe
Procedure
1. Fill the syringe with flushing solution.
2. Inject it into the inlet of the flow cell and allow it to act for
5 minutes.
3. Fill the syringe with water and inject again.
4. Remove the flow cell from the detector and use a nitrogen
stream to dry it.
Result
Flow cell is clean.
Next steps
Check, if the baseline noise has disappeared.
If the flushing does not have the desired effect, all flow cells can
be disassembled to clean the lens.
