PRONOVA FOS/TAC 2000, Руководство пользователя

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FOS/TAC 2000 MAINTENANCE, REPAIR, CUSTOMER SERVICE
812-04.2015-EN FOS/TAC 2000 User Manual 19
9.1 Maintenance of the pH electrode
On completion of the measuring process, always rinse the electrode, dry and dip in KCl solution. For this purpose, fill KCl solution
into the protective sleeve to a level of approx. 10mm and push the sleeve over the electrode. In order to prevent drying out, check
the filling level in the cap and, if necessary, top up if the electrode has not been in use for a longer period of time.
During transport or storage, KCl solution can leak from the protective cap and produce crystalline, white potassium chloride. This
salt layer has no influence on measuring capability and can be easily rinsed off with water.
An extended response time, a reduced gradient or an offset shift can be caused either by electrode soiling or ageing. Every
electrode ages as a consequence of the exchange processes at the glass membrane even if the electrode is not used. High
temperatures, polarization, short circuit or exposure to chemicals can significantly reduce the life of the electrodes. In the case of
electrodes with the possibility to top up electrolyte, the fluid level of the electrolyte solution must be checked at regular intervals. The
level of the reference electrolyte must always be several centimetres above the fluid level of the measuring solution. When
necessary, KCl solution (3mol/l) must be topped up with the syringe through the refill opening at the shaft after removal of the seal.
When changing the electrode, it is important to ensure
that the protective basket is adjusted as shown in the
illustration when the new electrode is fitted.
9.2 Changing the hose of the peristaltic pump
The hose of the peristaltic pump should be changed after approx. 250 measurements, but in no case later than after one year.
Possibility of aggressive media residues.
Wear protective glasses and suitable protective clothing when dismantling, repairing or cleaning the pump!
Before changing the pump hose, proceed as follows in order to drain the hoses:
Place an empty beaker onto the magnetic stirrer and pull the suction hose from the bottle containing the titration solution.
In the main menu, select the “Calibration” option and subsequently “Peristaltic pump” and press <OK> in order to start the pump.
The process ends automatically after two minutes or it can be stopped earlier by pressing <ESC>.
Calibration
Peristaltic
Pump with
< OK > Calibration
active
__________
OK
Calibration
pH Electrode
Perist. Pump
Measuring
Calibration
Stirrer
A/D Values
OK
OK