Waltron 9072, Руководство пользователя

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Waltron User Manual 101-054-A.1
9072 Hydrazine Analyzer
MAINTENANCE
6
MAINTENANCE
6.1 CLEANING OF ELECTRODES
Reference electrode: The surface of the reference electrode is made of silver chloride
(AgCl), by a galvanic process, and must not be cleaned.
Measuring electrode: The measuring electrode has to be cleaned (activated) if the
sensitivity (k-Factor) of the measuring electrode is beneath 10 % of the determined value,
calculated after that calibration, which followed a cleaning. As discussed above, the k-
Factor can be looked up in the menu Parameter > in the 7
th
level.
Before you remove the measuring electrode, it is necessary to empty the analyzer (of
sample). Then remove the plug (M) from the measuring electrode and unscrew the thrust
screw of the electrode. Take the electrode slowly out of the cell. You should be careful
not to drop the measuring electrode and not to hit it against the cell wall. Clean the
surface with a mild detergent, by rubbing gently the electrode between your middle
finger, index finger and thumb. During the cleaning, do not press too hard the electrode.
This procedure should not last longer than 2 minutes (the Pt-layer is only several µ m
thick). Rinse well with water and do not touch the surface of the electrode with your
fingers thereafter.
Occasionally a wiping of the electrode surface with a clean tissue is sufficient. Thereby
you reduce the later start up time until steady state condition.
6.2 CLEANING OF CELLS
The cleaning cycle of both the counter electrodes of the measuring and calibration cells is
the same as those of the measuring electrode and calibration electrode. To clean the
counter electrodes, you close the inlet valve and remove the plug connectors (A), (K) for
the calibration cell, as well as (M), (C) and (R) for the measuring cell. Disconnect the
pipe between the calibration cell and the flowmeter. Disassemble the calibration cell from
the square mounting by detaching the fitting (screw width SW 12 mm). Remove the
calibration electrode (see also the instruction for cleaning electrodes above). Clean the
interior with a mild detergent and a thin test tube brush (see also “Spare parts“). Examine,
if the nozzle in the top part (diameter
∅
0.8 mm) is free. After the cleaning you have to
rinse the cell well with water. The dismantling of the measuring cell from the square
mounting should be performed in the same way as the calibration cell. Remove the outlet
pipe and unscrew the reference cell from the measuring cell (see also
Section 4.2 ). Take
the electrode slowly out of the cell (see also Section 6.1 ). The cleaning procedure
thereafter is the same, as described for the calibration cell.
When reassembling, make sure that all parts are dry.