Endress+Hauser StamoLys CA 71 HY, Руководство по эксплуатации

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Maintenance Stamolys CA71HY
34 Hauser
7.2.1 Checking reagents
1. Check the concentration of the standard in the laboratory. Adapt the values (PARAMETER
ENTRY, calibration solution") or replace the standard solution.
2. Mix 10 ml standard solution and 5 ml of each reagent in a beaker. You must replace the
reagents if there is no visible coloration after max. ten minutes.
The finished mixture must be free of particles.
The reagents must be replaced if no visual coloration (blue) occurs after max. 2 minutes or if the
mixture is not free of particles.
7.2.2 Replacing reagents
1. Carefully remove the hoses from the canisters and wipe them with a dry (paper) towel. Wear
protective gloves when doing this.
2. Switch on the reagent pump for about 5 seconds.
3. Flush the reagent hose with plenty of distilled water (see SERVICE).
For this purpose, place a beaker with distilled water into the device.
4. Replace the reagent canisters and feed the hoses into the new canisters.
5. Fill the reagent hose with the new reagents (SERVICE). Switch all pumps to "g" for this
purpose. Do not switch the pumps off ("s") until no more air bubbles are to be seen in the hoses.
6. Determine the reagent blank value by using deionized water as a sample (see
"CONFIGURATION").
The value determined is saved by the analyzer as the frequency offset.
7. Then carry out a calibration (see chapter "Calibration").
7.3 Replacing pump hoses
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Warning!
When removing hoses from the hose nozzles, beware of reagent splashing.
For this reason, wear protective clothing, gloves and goggles.
The peristaltic pumps used for the analyzer convey the medium in a combination of vacuum and
displacement pump. The pump rate is dependent on the elasticity of the pump hoses. Elasticity
decreases and the pump rate drops as mechanical stress increases. Wear depends on mechanical
stress (measuring interval, pump pressure). Up to a certain degree, the wear effect can be
compensated by calibration. If the impairment in hose elasticity is too great, the pump rate is no
longer reproducible and this leads to incorrect measurements. This is why it is necessary to replace
the hoses.
Removing the old hoses
1. Remove the reagent hoses from the reagent canisters in order to prevent contamination of the
reagents.
2. Flush the old hoses with water first and then with air to empty them (see SERVICE).
3. Remove the hoses from the nipples of the hose boxes ( →
å
20, item 5).
4. Release the hose box(es) (1 to 3 per pump):
– Press against the lower retainer (item 3).
– You can now remove the hose box along with the pump hose.
– Remove the old hose from the case any dispose of it.
– Clean the hose box and the roller head (item 1) with water.