Amersham Pharmacia Biotech AKTA design pH/C-900, Руководство пользователя

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If these procedures fail to rejuvenate the electrode, the problem is
most likely a clogged liquid junction.
1 Heat a 1 M KNO
3
solution to 60 - 80°C.
2 Place the electrode tip in the heated KNO
3
solution.
3 Allow the electrode to cool while immersed in the KNO
3
solution
before re-testing.
If these steps fail to improve the electrode response, replace the
electrode.
4.4 Changing pH electrode
See section 2.4 Installing the pH electrode.
4.5 Cleaning the conductivity flow cell
If the conductivity measurements are not comparable to previous
results, the electrodes in the flow cell may be contaminated and
require cleaning. To clean the flow cell:
1 Pump 15 ml of 1 M NaOH at 1 ml/min through the flow cell
either by using a pump or a syringe.
2 Leave it for 15 minutes.
3 Rinse thoroughly with 50 ml de-ionised water.
Note: If the flow cell is totally blocked, the blockage can be broken
using a thin needle or a piece of string with a diameter less than
0.8 mm.
4.6 Changing conductivity flow cells
The flow cells can be changed when required. Make sure the
instrument is switched off, before disconnecting/connecting the cells
to the rear of the instrument housing.
1 If the cell is replaced with a new flow cell, the monitor must be
calibrated with the new cell constant value which is written on
the flow cell package. See sub menu
Setup conductivity
in section
B.2.3 in Reference information. If the cell constant is not known,
it can be determined (see section B.2.2 in Reference information).
4.7 Instrument housing
Wipe the instrument housing regularly with a damp cloth. Let the
instrument dry completely before use.
Monitor pH/C-900
User Manual 18-1120-06 Edition AC 14
4
Maintenance
18-1120-06_AC.qxd 1999-04-14 14:16 Sida 14 (1,1)