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Maintenance and care
AZURA® Conductivity Monitor CM 2.1S Instructions, V6710
Process
Figure
5.
Reset the settings to the facto-
ry settings (see chapter 5.2.2),
perform a function test (see
chapter 6) if necessary and
readjust the calibration points
Attach the capillaries and plug in the power plug.
Note:
The settings that were suitable for the operation of the disassem-
bled cell are still stored in the monitor. KNAUER recommends performing
a function test with the newly assembled cell according to Chapter 6 and,
if necessary, optimizing the settings according to Chapters 5.6 and 5.7 for
the new cell.
8.5 Flushing and cleaning the pH monitor
Note:
The pH electrode has a limited lifetime and should be replaced
every 6 months.
Note:
The pH flow cell and the pH electrode can be cleaned together
(recommended), but can also be rinsed separately by hand. In the flow,
the flow cell and electrode can only be cleaned together.
8.5.1 Cleaning pH electrode
A dirty pH electrode can lead to erroneous pH readings, delayed mea-
surement results and shorten the lifetime of the electrode. Most contam-
nant’s will be either proteins that have adsorbed onto the glass membra-
ne or buffer and salt crystals that have blocked the pH probe pores.
Removal of protein deposits:
Immerse the electrode in a 1 % solution of
proteases, such as trypsin or pepsin, in 0.1 M HCl for no more than
5 minutes. Rinse with deionized water to remove all traces of HCl.
Removal of salt deposits:
Immerse the electrode in 0.1 M HCl for 5 minu-
tes followed by 0.1 M NaOH for 5 minutes and then 0.1 M HCl for 5 minu-
tes. Rinse the electrode with deionized water to remove all traces of HCl.
8.5.2 Cleaning pH flow cell
If the pH flow cell is separated from the pH electrode, all agents suitable
for PEEK surfaces can be used for manual cleaning. Cleaning in an ultra-
sonic bath is also possible.
Store the pH electrode or return it to the pH flow cell and condition
it. For storage, separate components and store according to storage
recommendations.
Next steps
Next steps