Endress+Hauser Stamolys CA71NO, Руководство по эксплуатации

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Maintenance
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reagents must be replaced. Shelf life can be prolonged by keeping the reagents in a dark, cool storage
place. The reagents absolutely must be replaced when:
• the reagents have been contaminated by sample (see "Trouble-shooting instructions")
• the reagents are too old
• the reagents have been spoilt by incorrect storage conditions or environmental influences.
Reagents check
a. Check the standard solution concentration in the laboratory. Adapt the values (PARAMETER
ENTRY, "Calibration solution") or replace the standard solution.
b. Mix 10 ml standard solution and 5 ml of each reagent in a vessel. You must replace the
reagents, if there is no visible colouration ten minutes later.
To replace the reagents proceed as follows:
1. Carefully remove the hoses from the canisters and wipe them with a dry (paper) cloth. 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).
4. Replace the reagent canister and feed the hoses into the new canister.
5. Fill the reagent hose with the new reagents (SERVICE). Switch all pumps to "g". If there are
no more air cushings to be seen in the hoses, switch the pumps to "s".
6. Determine the reagent blank value by using destilled water as a sample (see chapter
"Calibration").
Enter the measured value as the frequency offset (CONFIGURATION / "Frequency offset").
7. Then carry out a calibration (see chapter "Calibration").
7.3 Replacing pump hoses
#
Warning!
When removing hoses from the hose nozzles, beware of reagent splashing.
For this reason, wear protective gloves, goggles and clothing.
The peristaltic pumps used for the analyser convey the medium as a combination of vacuum and
displacement pump. The pump rate is dependent on the elasticity of the pump hoses. Elasticity
decreases as mechanical stress increases and the pump rate drops. Wear depends on mechanical
stress (measuring interval, pump starting pressure). Up to a certain degree, the wear-effect can be
compensated by calibration. If the elasticity is too low, the pump rate is no longer reproducible
which leads to incorrect measurements. This is why it is necessary to replace the hoses.
Removing the old hoses:
1. Rinse the old hoses first with water and then with air to empty them (see SERVICE).
2. Remove the hoses from the connecting nipples on the pumps (
→
å
17, pos. 5).
3. Remove the reagent hoses from the reagent canisters, in order to prevent contamination of the
reagents.
4. Loosen the hose cassette(s) (1 to 3 per pump):
– Press against the lower holder (pos. 3).
– Now you can remove the cassette with the hose.
– Remove the hose from the cassette and dispose of it.
– Clean the cassette and the wheel head (pos. 1) with water.